unit 4 probability scientific inquiry and analysis1
TRANSCRIPT
SCIENTIFIC INQUIRY AND ANALYSIS 2
OBJECTIVES UNIT 4
The student will be able to:• Describe events as subsets of a set of outcomes using
characteristics or categories of the outcomes, or as unions, intersections, or complements of other events (“or”, “and”, “not”.) (CCSS.HSS.CP.A.1)
• Find the number of ways a group of objects can be arranged in order (permutations with and without replacement). (CCSS.HSS.CP.B.9)
• Find the number of ways to choose several objects from a group without regard to order (combinations with and without replacement). (CCSS.HSS.CP.B.9)
SCIENTIFIC INQUIRY AND ANALYSIS 3
OBJECTIVES UNIT 4
• Find the probability of simple and compound events. (5.3.12.C1)
• Determine if two events are independent by showing P(A given B) is the same as P(A) and that the P(B given A) is the same as P(B). (CCSS.HSS.CP.A.2, CCSS.HSS.CP.A.3)
• Find conditional probabilities as probability of A given B as P(A and B)/P(B). (CCSS.HSS.CP.B.6)
• Use the multiplication rule to find the probability of two events occurring in a sequence and to find conditional probabilities. (CCSS.HSS.CP. B.8)
• Use the addition rule to find the probability of two events. (CCSS.HSS.CP.B.7)
SCIENTIFIC INQUIRY AND ANALYSIS 4
PROBABILITY
• Probability – the numerical measure of the likelihood of an event occurring.
• Statistics – collection of methods for planning experiments, obtaining data, and then organizing, summarizing, presenting, analyzing, interpreting, and drawing conclusions from the data.
SCIENTIFIC INQUIRY AND ANALYSIS 5
PROBABILITY
• Sample Space– Before analyzing the probability that something
can occur, it is necessary to understand the number of possible outcomes given a set of possible choices or selections. This is known as the sample space.
SCIENTIFIC INQUIRY AND ANALYSIS 6
PROBABILITY
• Fundamental Counting Principle– When determining the number of possible
outcomes of an event, it is always not practical to count all of the outcomes. All of the possible outcomes is the sample space.
• One method to use to find the sample space is to use the Tree – Method.
• Another method to use to find the sample space is to us the Grid – Method. The grid – method is best if the number of selections is no more than 2.
SCIENTIFIC INQUIRY AND ANALYSIS 7
PROBABILITY
• Sample Space: (example using tree method) If you have a pair of blue pants, a pair of black pants, a white shirt and a red shirt, how many different ways can you wear one of your pants and one of your shirts? What are the events in this example?
SCIENTIFIC INQUIRY AND ANALYSIS 8
PROBABILITY
• Sample Space: (example using grid method) If you have a pair of blue pants, a pair of black pants, a white shirt and a blue shirt, how many different ways can you wear one of your pants and one of your shirts?
White Shirt Blue Shirt
Blue Pants White Shirt & Blue Pants
Blue Shirt & Blue Pants
Black Pants White Shirt & Black Pants
Blue Shirt & Black Pants
SCIENTIFIC INQUIRY AND ANALYSIS 9
PROBABILITY
• Counting Example 1:– Kevin goes to a sandwich shop to order a
sandwich. There is a choice of 5 different breads, 8 different meats, 5 different cheeses and 3 different condiments.
• If Kevin chooses one of each, determine how many different sandwiches can be made through a tree diagram?
SCIENTIFIC INQUIRY AND ANALYSIS 10
PROBABILITY
• Counting Example 1:
WHOLE WHEAT BREAD
HONEY HAM
SALAMI
BOILED HAM
PASTRAMI
ROAST BEEF
TURKEY
CHICKEN
BOLAGNA
SWISS CHEESE
PROVOLONE
AMERICAN CHEESE
CHEDDAR CHEESE
MUENSTER CHEESE
MAYO
OLIVE OIL
MUSTARD
SCIENTIFIC INQUIRY AND ANALYSIS 11
PROBABILITY
• Fundamental Counting Principle (Product Rule)– Instead of counting out every different occurrence
through a tree diagram, the fundamental counting principle is used to determine the number of occurrences.
– Principle: if one event can occur in m ways and another event can occur in n ways, then the number of ways that both events can occur is equal to m · n. (or m · n · o · p · q · r . . .)
SCIENTIFIC INQUIRY AND ANALYSIS 12
PROBABILITY
• Counting Example 1:– So, if we revisit this example, use the counting
principle to answer the question.– Jonah goes to a sandwich shop to order a
sandwich. There is a choice of 5 different breads, 8 different meats, 5 different cheeses and 3 different condiments.
• If Jonah chooses one of each, how many different sandwiches can be made?
SCIENTIFIC INQUIRY AND ANALYSIS 13
PROBABILITY
• Fundamental Counting Principle without Repetition– Example: Conner goes to a sandwich shop the next
day to order a sandwich. Again, there is a choice of 5 different breads, 8 different meats, 5 different cheeses and 3 different condiments.
• Conner is feeling hungrier than Jonah. If Conner chooses three different meats and one each of everything else, how many different sandwiches can be made? So, for this problem, you can’t repeat the type of meat.
SCIENTIFIC INQUIRY AND ANALYSIS 14
WHOLE WHEAT BREAD
HONEY HAM
SALAMI
BOILED HAM
PASTRAMI
ROAST BEEF
TURKEY
CHICKEN
BOLAGNA
SWISS CHEESE
PROVOLONE
AMERICAN CHEESE
CHEDDAR CHEESE
MUENSTER CHEESE
MAYO
OLIVE OIL
MUSTARD
SALAMI
PASTRAMI
ROAST BEEF
TURKEY
CHICKEN
BOLAGNA
HONEY HAM
SALAMI
PASTRAMI
ROAST BEEF
TURKEY
CHICKEN
BOLAGNA
PROBABILITY
• Fundamental Counting Principle without Repetition
SCIENTIFIC INQUIRY AND ANALYSIS 15
PROBABILITY
• Fundamental Counting Principle without Repetition– If one event (choosing the first meat) can occur m
ways, if that same event is done a second time (choosing the second meat) and if you don’t want the same outcome (the same meat twice, no repetitions), then the second event can occur m – 1 ways. Likewise, if the same event is done a third time (choosing a third meat) and if you don’t want the same outcome (no repetitions of the meat), then the third event can occur m – 2 ways.
SCIENTIFIC INQUIRY AND ANALYSIS 16
PROBABILITY
• Fundamental Counting Principle without Repetition– So, if we revisit this example, use the counting principle
without repetitions to answer the question.– Connor goes to a sandwich shop the next day to order a
sandwich. Again, there is a choice of 5 different breads, 8 different meats, 5 different cheeses and 3 different condiments.
• Conner is feeling hungrier than Jonah. If Conner chooses three different meats and one each of everything else, how many different sandwiches can be made? So, for this problem, you can’t repeat the type of meat.
SCIENTIFIC INQUIRY AND ANALYSIS 17
PROBABILITY
• Fundamental Counting Principle with Repetition– Assuming the same example, Mike goes to a
sandwich shop to order a sandwich and the choices are the same.
• Again Mike is feeling hungrier than Jonah. If Mike chooses three meats, but for this example he can choose each meat more than once, how many different sandwiches can be made?
SCIENTIFIC INQUIRY AND ANALYSIS 18
PROBABILITY
• Counting Principle Example– In a high school, there are 273 freshmen, 291
sophomores, 252 juniors and 237 seniors. In how many different ways can a committee of 1 freshman, 1 sophomore, 1 junior and 1 senior be chosen?
SCIENTIFIC INQUIRY AND ANALYSIS 19
PROBABILITY
• Fundamental Counting Principle (Sum Rule)– Instead of counting out every different occurrence
the fundamental counting principle is used to determine the number of occurrences.
– Principle: if one event can be chosen from two disjoint groups, then the number of ways that the event can occur is equal to m + n. (or m + n + o + p + q + r . . .)
SCIENTIFIC INQUIRY AND ANALYSIS 20
PROBABILITY
• Fundamental Counting Principle (Sum Rule)– Example: Chris goes into a restaurant and can
choose between 4 different chicken entrees or 3 different beef entrees or 5 different pasta entrees or 5 different seafood entrees. If he has one entrée, how many different entrees can he have? If he has two entrees, how many different ways can he order?
SCIENTIFIC INQUIRY AND ANALYSIS 21
PROBABILITY
• Factorials– Factorial (m!) is a mathematical operation that
multiplies a number m by this method :
– Example:
– Note: 1! = 1 & 0! = 1
𝑚× (𝑚−1 ) ×(𝑚−2)⋯×1
SCIENTIFIC INQUIRY AND ANALYSIS 22
PROBABILITY
• Permutations – determines the number of ways n elements (objects) can be arranged in order r ways.
• Permutation is calculated by figuring out the factorial.
• P(n,r) is sometimes phrased: “Permutations of n taken r times”
SCIENTIFIC INQUIRY AND ANALYSIS 24
PROBABILITY
• Permutation Example 1:– You are manager of a baseball team. You have 9
players on the team who can bat anywhere in the batting order. (i.e. 1st, 2nd, 3rd, 4th . . . 9th). How many different batting orders could you have?
SCIENTIFIC INQUIRY AND ANALYSIS 25
PROBABILITY
• Permutation Example 2:– You have 9 players that can bat in the first 3
positions of the batting order. How many different ways can the manager arrange the first 3 positions of the batting order?
SCIENTIFIC INQUIRY AND ANALYSIS 26
PROBABILITY
• Permutation Example 3:– Next year you are taking Calculus I, Intro to
Engineering, Spanish II, Phys Ed, Physics I, American Literature, US History, Chemistry. Assume each class is offered during each of the 8 periods of the day. In how many different orders can you schedule your classes?
SCIENTIFIC INQUIRY AND ANALYSIS 27
PROBABILITY
• Permutations with Repetition: for the permutations taken so far, all of the objects were distinct. If they are not distinct, then the permutations are not indistinguishable.
• For example: How many orders of three are there of the letters M – O – M? Which means how many permutations of the 3 letters take 3 ways:
• However some of the outcomes are not indistinguishable.
MOM, OMM, MMO, MOM OMM, MMO• In this case only 3 outcomes are distinguishable.
SCIENTIFIC INQUIRY AND ANALYSIS 28
PROBABILITY
• Permutations with Repetition: the number of distinguishable permutations of n objects where one object is repeated q1 times, another is repeated q2 times, etc.
SCIENTIFIC INQUIRY AND ANALYSIS 29
PROBABILITY
• Permutation with Repetition Example 1:– Find the number of distinguishable permutations
of the letters in REBECCA.
SCIENTIFIC INQUIRY AND ANALYSIS 30
PROBABILITY
• When not concerned with the order of an outcome, it is known at a combination.
• Examples:– Being dealt 5 cards in a card game. Not concerned
with the order.– Ordering an omelet with 1 cheese, 1 meat and 1
vegetable.
SCIENTIFIC INQUIRY AND ANALYSIS 31
PROBABILITY
• Combinations – how many different r objects out of n objects, no order.
• Given the same number of n objects and r objects, which is larger the combination or the permutation?
SCIENTIFIC INQUIRY AND ANALYSIS 32
PROBABILITY
• Combination Example 1:– You have 9 players that can bat in the first 3
positions of the batting order. How many different combinations of players can the manager utilize to fill in the first 3 positions of the batting order?
– Remember: it is not important that the 3 players selected to bat in the 3 positions bat 1st, 2nd or 3rd. Compare this to permutation example 2.
SCIENTIFIC INQUIRY AND ANALYSIS 33
PROBABILITY
• Combination Example 2:– You are dealt 4 cards out of regular deck of 52.
How many different combinations of the 4 cards out of the 52 can you get?
SCIENTIFIC INQUIRY AND ANALYSIS 34
PROBABILITY
• Multiple Combination Events– Sometimes there are multiple combination events
which require you to calculate multiple times and then either multiply them or add them together.
– For example you are dealt 7 cards out of 52. How many possible ways are there of getting 7 cards all of the same suit? OR
– There are 5 field day events and you have to participate in at least 2 events. How many different combination of events can you participate?
SCIENTIFIC INQUIRY AND ANALYSIS 35
PROBABILITY
• Multiple Combination Events (Multiplication)– When finding the number of ways both one event
(Event A) and another event (Event B) can occur, take the combination of both and multiply the two together.
– Example: you are dealt 7 cards out of 52. How many are all of the same suit?
Event A (chose 1 out 4 suits)
Event B (chose 7 out of 13 cards in a suit)
SCIENTIFIC INQUIRY AND ANALYSIS 36
PROBABILITY
• DO NOW Problem– Have out your homework.– Do the following problem:
You are packing for a vacation. At home you have 10 shirts and 7 pairs of shorts.
1. In how many different ways can you choose 4 pairs of shorts to take on vacation?
2. In how many different ways can you choose 2 shirts to wear on the 1st and 2nd days of vacation?
3. If you bring 4 pairs of shorts and 6 shirts, how many different outfits can you make?
SCIENTIFIC INQUIRY AND ANALYSIS 37
PROBABILITY
• Probability – a number between 0 – 1 which indicates the likelihood the event will occur.– Experiment – a process by which an outcome is
obtained.– Sample Space (S) – a set that is composed of a
finite number of possible outcomes.– Event (E) – any subset of the sample space.
38
PROBABILITY
• Probability– Probability of an outcome in E will occur is the
ratio of the number of outcomes in E to the number of outcomes in Sample Space (S).
SCIENTIFIC INQUIRY AND ANALYSIS
OUTCOMES
SAMPLE SPACE (S)
EVENT (E)
SCIENTIFIC INQUIRY AND ANALYSIS 39
PROBABILITY
• Probability OUTCOMES
SAMPLE SPACE (S)
EVENT (A)
𝑃 ( 𝐴)= 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑜𝑢𝑡𝑐𝑜𝑚𝑒𝑠𝑖𝑛 𝐴𝑡𝑜𝑡𝑎𝑙𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑜𝑢𝑡𝑐𝑜𝑚𝑒𝑠
SCIENTIFIC INQUIRY AND ANALYSIS 40
PROBABILITY
• Example– Experiment – draw two cards out of a deck of 52
cards. What is the probability both will be a red face card?
– Sample Space (S) = # of ways to select two cards out of deck of 52.
– Event (E) = # of ways to get two red face cards.– Probability (P) =
SCIENTIFIC INQUIRY AND ANALYSIS 42
PROBABILITY
• Example of Punnett Square– Experiment – genes that determine eye color are
either Aa or Bb. Each parent contributes an A or a gene and a B or b gene. What is the probability that a baby whose parents are both AaBb will have green eyes? (3 lower case, 1 upper case)
– Sample Space (S) = – Event (E) = – Probability (P) =
SCIENTIFIC INQUIRY AND ANALYSIS 43
PROBABILITY
• Combination/Probability Example:– The graph shows the % of 100
pizzas sold according to type. If 3 pizza were randomly chosen out of the 100, what is the probability that all 3 were thin crusts?
– Sample Space (S) = combinations of 3 pizzas out of all 100 pizzas
– Event (E) = combinations of 3 thin crust pizza
– Probability (P) =
Thin Crust53%
Pan Pizza22%
Thick Crust23%
Stuffed Crust2%
Pizzas Sold
SCIENTIFIC INQUIRY AND ANALYSIS 44
PROBABILITY
• Counting Principle Probability Example:– GP Clayton goes to a sandwich shop to order a
sandwich. There is a choice of 5 different breads, 8 different meats, 5 different cheeses and 3 different condiments.
• If GP Clayton chooses one of each, how many different sandwiches can be made?
# of sandwiches = 5 x 8 x 5 x 3 = 600
SCIENTIFIC INQUIRY AND ANALYSIS 45
PROBABILITY
• Counting Principle Probability Example (Continued):
• Orest ran out of turkey. He is wondering what is the probability that GP Clayton will ask for a sandwich with turkey?
– Sample Space (S) = the number of sandwiches that can be made.
– Event (E) = the number of sandwiches with turkey– Probability (P) =
SCIENTIFIC INQUIRY AND ANALYSIS 46
PROBABILITY
• Counting Principle Probability Example (Continued):
• Orest ran out of salami and Swiss cheese. He is wondering what is the probability that Kevin will ask for a sandwich with salami or Swiss?
– Sample Space (S) = the number of sandwiches that can be made.
– Event (E) = the number of sandwiches with salami or the number of sandwiches with Swiss
– Probability (P) =
SCIENTIFIC INQUIRY AND ANALYSIS 47
PROBABILITY
• Geometric Probability:– Using a particular geometric shape to represent the
event space and the whole geometric shape represents the sample space.
– Example: given the blue square is 10’ x 10’ and the orange square is 7’ x 7’, what is the probability that a dart will fall in the orange square.
SCIENTIFIC INQUIRY AND ANALYSIS 48
PROBABILITY
• Empirical Probability - the ratio of the number of favorable outcomes to the total number of trials.
• Law of Large Numbers– The theorem that describes the result of performing
the same experiment a large number of times. According to the law, the average of the results obtained from a large number of trials should be close to the expected value, and will tend to become closer as more trials are performed.
SCIENTIFIC INQUIRY AND ANALYSIS 49
PROBABILITY
• Example of Telephone Numbers– Experiment – What is the probability that given a
telephone book page that a telephone number ends in 1?, 2?, 3?, 4?, 5?, 6?, 7?, 8?, 9?, 0?
– Theoretical Probability (P) = – Sample Space (S) =
SCIENTIFIC INQUIRY AND ANALYSIS 50
PROBABILITY• Example of Telephone Numbers
EVENT NUMBER OF OUTCOMES
FREQUENCY = # OF OUTCOMES/SAMPLE SPACE
Telephone # ends in 1
Telephone # ends in 2
Telephone # ends in 3
Telephone # ends in 4
Telephone # ends in 5
Telephone # ends in 6
Telephone # ends in 7
Telephone # ends in 8
Telephone # ends in 9
Telephone # ends in 0
SCIENTIFIC INQUIRY AND ANALYSIS 51
PROBABILITY
• DO NOW – As part of a monthly inspection at a hospital, the
inspection team randomly selects reports from 8 of the 84 nurses who are on duty. What is the probability that none of the reports selected will be from the 10 most experienced nurses on duty? OR What is the probability that all of the reports selected will be from the 74 least experienced nurses on duty?
SCIENTIFIC INQUIRY AND ANALYSIS 52
PROBABILITY
• Unions & Intersections Review– A SET is a collection of elements.
• For example Set A can be made up of the numbers {2, 3, 6, 8} Set B can be made up of the numbers {2, 6, 9, 12}
– A UNION of sets A or B means that the elements belong to either SETS A or B.
– An INTERSECTION of sets A and B means that the elements belong to SETS A and B
SCIENTIFIC INQUIRY AND ANALYSIS 54
PROBABILITY
• Probabilities of Unions & Intersections
– If A and B are events in the same sample space, then the probability of A or B occurring is:
P(A U B) = P(A) + P(B) – P(A ∩ B)
P(A U B) can also be written P(A or B)
P(A ∩ B) can also be written P(A and B)
SCIENTIFIC INQUIRY AND ANALYSIS 55
PROBABILITY
• Probabilities of Unions & Intersections
– If A and B are mutually exclusive events in the same sample space, then the probability of A or B occurring is:
P(A U B) = P(A) + P(B)
SCIENTIFIC INQUIRY AND ANALYSIS 56
PROBABILITY
• Union Example 1:– One card is selected from a standard deck of 52
playing cards. What is the probability that the card is a heart or a face card?
P(A or B) = P(A) + P(B) – P(A and B)
SCIENTIFIC INQUIRY AND ANALYSIS 57
PROBABILITY
• Union Example 2:– One card is selected from a standard deck of 52
playing cards. What is the probability that the card is a heart or a diamond card?
P(A or B) = P(A) + P(B) – P(A and B)
SCIENTIFIC INQUIRY AND ANALYSIS 58
PROBABILITY
• Union Example 3:– In a poll of HS juniors, 6 out of 15 took a French
class and 11 out 15 took a math class. Fourteen out of 15 students took French or Math. What is the probability that a student took both French and Math?
P(A or B) = P(A) = P(B) =P(A and B) =
SCIENTIFIC INQUIRY AND ANALYSIS 59
PROBABILITY
• Complements
– If A is an event in a sample space X, then the event consisting of all outcomes in X that are not in A is called the complement, A’:
P(A’) = 1 - P(A)
A’ A
SCIENTIFIC INQUIRY AND ANALYSIS 60
PROBABILITY
• Complement Example 1:– In throwing two 6 sided dice what is the
probability that the sum is not 11?
SCIENTIFIC INQUIRY AND ANALYSIS 61
PROBABILITY
• Example 2:– The freezer case at a grocery store contains several
frozen pies: 10 apple, 4 peach, 6 blueberry, 5 pumpkin, 3 peanut butter, and some pecan. You are shopping in a hurry and pick one of the pies from the freezer without looking at the type. The probability that the pie you picked is apple or pecan is 13/22. How many pecan pies are in the freezer case?
SCIENTIFIC INQUIRY AND ANALYSIS 62
PROBABILITY
• DO NOW – A deck of UNO cards is made up of 108 cards.
(Twenty five each of red, yellow, blue and green, and 8 are wild cards). Each player is randomly dealt a 7 card hand.
• What is the probability that a hand will have 2 wild cards?
• What is the probability that a hand will have 2 wild cards, 2 red cards and 3 blue cards?
• What is the probability that a hand will have at least 2 wild cards?
SCIENTIFIC INQUIRY AND ANALYSIS 63
PROBABILITY
• Independent Events– Two events are independent if the occurrence of
one has no effect on the occurrence of the other.– Given A & B are independent events, the
probability that A & B occur is:
P(A ∩ B) = P(A) · P(B)
Remember that P(A ∩ B) can be written P(A and B)
SCIENTIFIC INQUIRY AND ANALYSIS 64
PROBABILITY
• Independent Events– When calculating probability of independent
events, the probability can be found on more than 2 independent events.
– Given A & B & C are independent events, the probability that A & B & C occur is:
P(A ∩ B ∩ C) = P(A) · P(B) · P(C)– Typically for independent events the sample space stays the
same.
SCIENTIFIC INQUIRY AND ANALYSIS 65
PROBABILITY
• Independent Event Example 1:– In a survey, 9 out of 11 men and 4 out of 7 women
said they were satisfied with a product. If the next 3 customers are 2 women and a man, what is the probability that they will all be satisfied?
SCIENTIFIC INQUIRY AND ANALYSIS 66
PROBABILITY
• Independent Event Example 2:– The following examples are better done using
complements.– Given the previous survey of example 1, what is
the probability that if men are the next 4 customers that at least 1 of them is not satisfied with the product?
– Given the previous survey of example 1, what is the probability that if men are the next 4 customers that all of them are not satisfied with the product?
SCIENTIFIC INQUIRY AND ANALYSIS 67
PROBABILITY
• Dependent Events– Two events are dependent if the occurrence of one
has an effect on the occurrence of the other.– Given A & B are dependent events, the probability
that A & B occur is:
P(A ∩ B) = P(A) · P(B|A)P(B|A) is known as a conditional probability that indicates
the probability that B occurs given that A has occurred.
SCIENTIFIC INQUIRY AND ANALYSIS 68
PROBABILITY
• Dependent Events– When calculating probability of dependent events,
the probability can be dependent on more than 2 events.
– Given A & B & C are dependent events, the probability that A & B & C occur is:
P(A ∩ B ∩ C) = P(A) · P(B|A) · P(C|A & B)
SCIENTIFIC INQUIRY AND ANALYSIS 69
PROBABILITY
• Dependent Event Example 1:– Three children have a choice of 12 summer camps
that they can attend. If they each randomly choose which camp to attend what is the probability that they all attended different camps?
SCIENTIFIC INQUIRY AND ANALYSIS 70
PROBABILITY
• Independent vs. Dependent Events– A box contains the numbers 1 – 20. What is the
probability of selecting 1 number less than 6, replacing the number and selecting a second number less than 6?
– Is this process dependent or independent?– How can the above event be changed to the
opposite type of event?
SCIENTIFIC INQUIRY AND ANALYSIS 71
PROBABILITY
• Example:– There are 25 pieces of paper, numbered 1 to 25, in
a hat. You pick a piece of paper, replace it and then pick another piece of paper. What is the probability that each number is greater than 20 or less than 4?
SCIENTIFIC INQUIRY AND ANALYSIS 72
PROBABILITY
• Complements (Review)– When finding the probability of something
occurring, it is sometimes easier to find the probability when something won’t occur (its complement) and then use the formula below.
P(A’) = 1 - P(A)
SCIENTIFIC INQUIRY AND ANALYSIS 73
PROBABILITY
• Complement Example:– Suppose that 1% of the lights in a shipment of 10,000
lights are defective. If you make 100 random tests of the lights (each time choosing, testing and replacing the light), what is the probability that at least one of the tests reveals a defective light.
– P(A’) = 9900 / 10,000 = 0.99 (selecting 1 good light)– P(A’)100 = 0.99100 ≈ 0.366 (selecting 100 good lights, 100
times)– P(A) = 1 - 0.99100 ≈ 0.634 (at least 1 bad after selecting
100)
SCIENTIFIC INQUIRY AND ANALYSIS 74
PROBABILITY
• DO NOW:In one town 95% of the students graduate from high school. Suppose a study showed that at age 25, 81% of the high school graduates held full-time jobs while only 63% of those who did not graduate held full-time jobs. What is the probability that a randomly selected student from the town will have a full time job at age 25?
SCIENTIFIC INQUIRY AND ANALYSIS 75
HOMEWORK UNIT 4-1 ANSWERS
• Homework Answers:– Pg. 705, 15 - 22.
15. 3 ways
16. 15 ways
17. 40 ways
18. 1512 ways
19. 17,576,000; 11,232,000
20. 45,697,600; 32,292,000
21. 6,760,000; 3,276,000
22. 118,813,760; 78,936,000
55. 480
56. 2772
57. 2,176,782,336; 1,402,410,240
SCIENTIFIC INQUIRY AND ANALYSIS 76
HOMEWORK UNIT 4-2 ANSWERS
Pg. 705
23. 40,320
24. 120
25. 3,628,800
26. 362,880
31. 6
32. 20
33. 2
34. 5040
Pg. 706
60. 3,628,800
61.a. 720
b. 60,480
62. 210
63.12,612,600
Pg. 712
22. 495
23. 1
24. 3003
25. 165
26. 792
27. 48
28. 778,320
Pg. 713
48. 1365
49. 315
52. 21,700
56. 210
SCIENTIFIC INQUIRY AND ANALYSIS 77
HOMEWORK UNIT 4-3 ANSWERS
Pg. 719
21. 0.5
22. 0.9231
23. 0.23
Pg. 720-721
30. 0.0218
31. 0.455
32. 0.477
33. 0.545
34. 0.262
35. 0.0385
36. 0.154
39. 5.6 x 10-8
40. 0.001
43. 0.0527
SCIENTIFIC INQUIRY AND ANALYSIS 78
HOMEWORK UNIT 4-4 ANSWERS
Pg. 719-721
24. Exp = 21.7%
Th = 16.7%
25. Exp = 30.8%
Th = 33.3%
26. Exp = 49.2%
Th = 50%
27. Exp = 50.8%
Th = 50%
37. 26.2%
38. 1.285 x 10-10
41. a. P(tv) = 55.5%
b. P(vid) = 3.8%
42. a. P(loss) = 23.5%
b. P(gains) = 64.7%
46. 4.0%
SCIENTIFIC INQUIRY AND ANALYSIS 79
PROBABILITY
DO NOW: The Supreme Court of the US has 3 women and 6 men justices. On a certain case the justices voted 5 to 4 in favor of the defendant.
1. What is the probability that exactly 2 out of 3 women voted in favor of the defendant?
2. What is the probability that at least 2 out of 3 women voted in favor of the defendant?
SCIENTIFIC INQUIRY AND ANALYSIS
HOMEWORK UNIT 4-5 ANSWERS
Pg. 727
4. 0.5
6. 0.5
8. 0.6
10. 0.1
12. 0.5
14. 0.67
16. 0.25
17. 0.7
18. 0.45 (yes)
25. 0.66
27. 0.25
Pg. 728
42. 0.83
43. 0.75
46. 0.1
47. 0.1
80
SCIENTIFIC INQUIRY AND ANALYSIS 81
PROBABILITY
DO NOW: Allergic reactions to poison ivy can be miserable. Plant oils cause the reaction. A study was performed to see the effects of washing the oil off within 5 minutes of exposure. A random sample of 1000 people with known allergies to poison ivy participated in the study. Oil from the poison ivy plant was rubbed on a patch of skin. For 500 of the subjects, the oil was washed off within 5 minutes. For the other 500 subjects, the oil was washed off after 5 minutes. The results are in the table:
HOMEWORK UNIT 4-6 ANSWERS
Pg. 734 & 73512. 0.046813. 0.046818.a. 0.0625 b. 0.063719.a. 0.0059 b. 0.006025. 0.0014426. 0.60633. 0.581
SCIENTIFIC INQUIRY AND ANALYSIS 82
SCIENTIFIC INQUIRY AND ANALYSIS 83
PROBABILITY
• DO NOW Problem– Have out your homework.– Do the following problem:
Radio station call letters (i.e. WNBC) consists of four letters beginning with either K or W. How many different radio station call letters are possible if letters can be repeated? How many different radio station call letters are possible if letters cannot be repeated?
SCIENTIFIC INQUIRY AND ANALYSIS 84
PROBABILITYEvaluate the following:
a) 4! =b) 12! =c) 3P3 =
d) 5P1 =
e) 10P1 + 5P2 =
f) 4P3 x 3P2 =
1. You are taking a Chemistry test and are given a list of
10 elements. You are to arrange the ten elements in order as they appear in the periodic table of elements. Suppose you have no idea of the correct order and simply guess. How many different ways can the ten elements be listed?
2. You are taking a Chemistry test and are given a list of 10 elements. You are told three of those elements are elements 5, 6 & 7 on the periodic table of elements. You are asked to pick elements 5, 6 & 7 and to arrange the three elements in order as they appear in the periodic table of elements. Suppose you have no idea of the correct elements or the correct order and simply guess. How many different ways can the three elements be listed? Suppose you know the three elements but you have no idea of the correct order and simply guess. How many different ways can the three elements be listed?
3. A student council is made up of 2 Freshmen, 2 Sophomores, 2 Juniors and 3 Seniors. There are 75 Freshman, 68 Sophomores, 71 Juniors and 82 Seniors. Selections for each class are done randomly where the first pick of the class is the active council member and subsequent picks are the alternates. The senior
class has two alternates and all of the other classes have only one alternate. How many different student councils can be formed?
SCIENTIFIC INQUIRY AND ANALYSIS 85
PROBABILITY1. Evaluate the following:a) 3C3 =
b) 1000C25 =
c) 4C3 x 6C2 =
d) 5C3 x 2C2 =
e) 5C1 + 8C2 =
f) 5P1 + 8P2 =
2. Seven cards are dealt from a regular 52 card deck. How many different ways can the seven cards be dealt?
3. To the right is an indication of how many students from the junior class are taking AP classes. Three students are picked from the junior class (order doesn’t matter). How many ways can those 3 students be chosen from the whole junior class? If only those students who took just 1 AP class were chosen, how many ways can they be selected? If only those students who took at least 1 AP class were chosen, how many ways can
they be selected?
4. There are 10 horses in a race. One of the bets in a horse race is the “exacta” in which you select the 2 horses for “win and place” (1st & 2nd places) in that exact order. How many exacta bets are possible in this race? The “quinella” bet is similar to the “exacta” in which you select the 2 horses for “win and place” (1st & 2nd
places), but it does not matter in what
order they finish. How many quinella bets are possible in this race?
• EXTRA: If you make 4 exacta bets in the race, what is the probability you select the correct one? If you make 4 quinella bets in the race, what is the probability you select the correct one?
36
14
8
12Junior Students
Took 1 AP Class Took 2 AP Classes
Took 3 AP Classes Took no AP Classes