Pre-AlgebraComparing and Scaling 2.3

Monday, September 8

Problem 2.2 ACE Questions #1 and #2 answers

What did we do last time 2.2

In investigation 2.2 we completed a table to pizza prices for Howdy and Royal PizzaWhat was the equation we came up with for Howdy’s pizza?How about for Royal Pizza?

Equation for Royal Pizza: P=12n

Equation for Howdy’s Pizza: P=13n

What does the 13 represent in the equation for Howdy’s pizza?

What does the 12 represent in the equation for Royal’s pizza?

Learning Target

I will be able to identify a unit rate in• a description, • an equation• a table, or • a graph.

Vocabulary

Constant of proportionality: The constant ratio of two proportional quantities, x and y; usually written as y = kx, where k is the constant of proportionality. For example in the equation y= ¾ x, the constant or proportionality is ¾. The graph for this relationship is shown below.

Who can tell me the definition of a unit rate?

Problem 2.3 A

Problem 2.3 A

Number of oranges (n)

10 5 1 20 11 13

Cost, C $2 $1 $.20 $4 $2.20 $2.60

Problem 2.3 A

Number of oranges (n)

10 5 1 20 11 13

Cost, C $2 $1 $.20 $4 $2.20 $2.60

Problem 2.3 A

Number of oranges (n)

10 5 1 20 11 13

Cost, C $2 $1 $.20 $4 $2.20 $2.60

5a. Every time the cost of oranges goes up by $1, the number of oranges increases by 5.

5b. C = .20n, this equation says that every time the number of oranges goes up by 1, the cost goes up by $.20.

5c. $.20/1 orange and 5 oranges/$1

5d. The constant of proportionality and the unit rate are the same.

Problem 2.3 B

Problem 2.3 B

Problem 2.3 B

Problem 2.3 C

Problem 2.3 C

Problem 2.3 C

4. Gus should buy the pasta at Fresh Foods, it is $.83/box.

Rate your understanding

I will be able to identify a unit rate in• a description, • an equation• a table, or • a graph.

Homework

ACE Questions P. 51 #9 and #10