7th Grade Math

GLE 0706.1.2 Apply and adapt a variety of appropriate strategies to problem solving, including estimation,

and reasonableness of the solution. Also addresses SPI 0706.2.1, SPI 0706.2.3.

Problem-Solving Investigation

1. Determine what height a ball would reach after the fourth bounce if it is
   dropped from 12 feet and bounces up _^23 as high.

Main Idea Solve problems by drawing a diagram.

Draw a Diagram

CACEY: I drop a ball from a height of 12 feet. It

hits the ground and bounces up half as high as it

fell. This is true for each successive bounce.

YOUR MISSION: Draw a diagram to find the height

the ball reaches after the fourth bounce.

Understand You know the ball is dropped from a height of 12 feet. It bounces up half as high.

Plan Draw a diagram to show the height of the ball after each bounce.

Solve

1234

12 ft

6 ft

3 ft

1 ft^12 ft 3

4

The ball reaches a height of _^34 foot after the fourth bounce.

Check Start at 12 feet. Multiply by^1 2 for each bounce: 12 · ^12 · ^12 · ^12 · ^12 = 1216 or _^34. ✓

Multiply and Divide Fractions

PART A B C D

Multi-Part

Lesson 3

166 Rational Numbers

166_167_PSI_895130.indd 166 12/31/09 12:42 PM