Percentage and Proportional Reasoning

This video tutorial covers Module 4, Lesson 6, focusing on percent formulas. It includes examples such as calculating percent increases in model car collections, determining the percentage of students taller than a certain height, computing tips as a percentage of a bill, expressing time as a percentage of a larger period, comparing rectangle dimensions using percentages, and calculating plant growth percentages.

If Corey has 80 model cars, which is 25% more than Everett, how many cars does Everett have?

• 60

• 80

• 64

• 70

In a class of 20 students, 75% are taller than 60 inches. How many students are taller than 60 inches?

• 10

• 18

• 12

• 15

Bobby's bill is $18, and she wants to leave a 15% tip. How much should the tip be?

• $2.70

• $2.50

• $2.00

• $3.00

Express 9 hours as a percentage of 3 days.

• 20%

• 15%

• 12.5%

• 10%

Richard works from 11 a.m. to 3 a.m. with a dinner break 75% through his shift. What time is his break?

• 12 a.m.

• 9 p.m.

• 10 p.m.

• 11 p.m.

If 370 fans cheer for School A and 555 for School B, what percent of School B's fans are School A's fans?

• 70%

• 60%

• 50%

• 66.7%

Rectangle A has a width of 8 cm and a length of 16 cm. Rectangle B has the same area but a width that is 62.5% of Rectangle A's width. What is the length of Rectangle B?

• 30 cm

• 25.6 cm

• 32 cm

• 20 cm

A plant grows from 40 inches to 48 inches in a week. What is the percentage increase in height?

• 25%

• 20%

• 30%

• 15%

Lauren needs a certain number of signatures for a petition. She has 672, which is 40% more than needed. How many signatures does she need?

• 540

• 480

• 500

• 520

If a rectangle's length is 160% of another rectangle's length, what percent more is it?

• 70%

• 60%

• 50%

• 40%