Warm Ups1) A student has completed 12 out of 34 homework assignments. At this
rate, how many assignments would the student complete out of 85 assignments.
2) To make a model of the Victoria River, Zoe used 2.5 inches of clay for every 7 miles of the actual river’s length. Her model river was 50 inches long. How long is the Victoria River?
Answers:
1) 30
2) 140
4 - 4 Percents
Day 2Objective: To solve ratio word problems and problems simple interest.
Standard 5.0
Similar Triangles (worksheet)
1. A vertical flagpole casts a shadow 12 ft long at the same time that a nearby vertical post 5 ft high casts a shadow 3 ft long. Find the height of the flagpole.
Similar Triangles (worksheet)
2. A vertical rod 8 ft high casts a shadow 6 ft long. At the same time, a nearby tree casts a shadow 15 feet long. Find the height of the tree.
Try #3 with partnerTry #4 on your own
3. 4.
Finish this worksheet for homework!!
Interest
Think about these questions..
What is it?
Where/When is it earned? Why?
Now discuss your answers with a partner.
I = prt
I = Interest earned ($)p = principle (amount put in) ($)r = interest rate (as a decimal) (%)t = time (in years) (yrs)
Example 1
Find p if I = $45, r = 6%, and t = ½ year
45 = p(0.06)(.5)
45 = .03p
p = $1500
TOO1. Find p if I = $196, r = 10%, t = 7 years.2. Find r if I = $120, p = $600, t = 5
years.
Answers:
1. p = $280
2. r = 4%
Example 2
Find I if p = $1500, r = 7%, and t = 18 months
*change months to years (÷ 12)
I = 1500(.07)(18/12)I = 105(1.5)I = $157.50
TOO
1. Find I if p = $500, r = 5%, t = 6 months.
2. Find t if I = $200, p = $1500, r = 1%.
Answers:
1. I = $12.502. t = 13.3 years = 13 years 4 months
HomeworkSimilar Triangles worksheet
Pg. 219 # 40-45 all