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 GLE 0706.1.5, SPI 0706.1.2, SPI 0706.2.3.

Multi-Part

Lesson 2

42 Expressions and Patterns

Problem-Solving Investigation

Understand Student Council members published 2 posts in August, 4 posts in September,

and 8 posts in October. You need to find the number of posts that they

published in January.

Plan Look for a pattern. Then extend the pattern to find the solution.

Solve The first three months, Student Council members published 2 posts, 4 posts, and

8 posts. Extend the pattern.

Months ASONDJ

Number of Posts 2 4 8 16 32 64

× 2 × 2 × 2 × 2 × 2

The Student Council published 64 posts in January.

Check Use counters or cubes to model the monthly pattern of published posts. Count

the number of objects used to represent published posts in January. ✔

Look for a Pattern

HOSHI: Last year, members of Student Council wrote

a blog for the school Web page. We used a rule to

determine the number of posts we would publish

each month. We published 2 posts in August,

4 posts in September, and 8 posts in October.

YOUR MISSION: Look for a pattern to find the

number of posts that Student Council members

published in January.

Main Idea Solve problems by looking for a pattern.

1. Suppose Student Council members published 2 posts in August, 6 posts in
   September, and 18 posts in October. Find the number of posts that Student
   Council members would publish in January.

MuMultlti-iPaPartr

Lesson Patterns

PART A BC

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