# Lesson 15

Finding This Percent of That

Let’s solve percentage problems like a pro.

### Problem 1

- To find 40% of 75, Priya calculates \(\frac{2}{5} \boldcdot 75\). Does her calculation give the correct value for 40% of 75? Explain or show how you know.
- If \(x\) represents a number, does \(\frac{2}{5} \boldcdot x\) always represent 40% of that number? Explain your reasoning.

### Problem 2

Han spent 75 minutes practicing the piano over the weekend. For each question, explain or show your reasoning.

- Priya practiced the violin for 152% as much time as Han practiced the piano. How long did she practice?
- Tyler practiced the clarinet for 64% as much time as Han practiced the piano. How long did he practice?

### Problem 3

Last Sunday 1,575 people visited the amusement park. 56% of the visitors were adults, 16% were teenagers, and 28% were children ages 12 and under. Find the number of adults, teenagers, and children that visited the park.

### Problem 4

Order from greatest to least:

- 55% of 180
- 300% of 26
- 12% of 700

### Problem 5

Complete each statement.

- 20% of 60 is ________
- 25% of ________ is 6
- ________% of 100 is 14

- 50% of 90 is ________
- 10% of ________ is 7
- 30% of 70 is ________

### Problem 6

A shopper needs 24 sandwich rolls. The store sells identical rolls in 2 differently sized packages. They sell a six-pack for $5.28 and a four-pack for $3.40. Should the shopper buy 4 six-packs or 6 four-packs? Explain your reasoning.

### Problem 7

On a field trip, there are 3 chaperones for every 20 students. There are 92 people on the trip. Answer these questions. If you get stuck, consider using a tape diagram.

- How many chaperones are there?
- How many children are there?