Fishtank Learning

3rd Grade Math
Unit 4: Area
Lesson 6

Objective

Find the area of a rectangle through multiplication of the side lengths.

Anchor Tasks - Problem 1

a.   The tick marks on the sides of the rectangle below are 1 unit apart.

Fishtank Learning curriculum image

What is the area in square units? Show or explain how you know.

b.   The top side of this rectangle is marked off in unit lengths. The left side is labeled with the length in units.

Fishtank Learning curriculum image

What is the area in square units? Show or explain how you know.

Anchor Tasks - Problem 2

a.   Write a multiplication expression that represents the area of the following figure. Then find its area.

Fishtank Learning curriculum image

b.   Frederick draws another rectangle with the same area. What might the length and width of Frederick's rectangle be?

Anchor Tasks - Problem 3

a.   The area of the rectangle below is 42 square units. Find the missing side length.

Fishtank Learning curriculum image

b.   Explain how you can use either multiplication or division to solve Part (a).

Problem Set

Target Task - Problem 1

A rectangle has the measurements shown. Select the three ways to calculate the area of the rectangle in square units.

Fishtank Learning curriculum image

A.   3 × 3

B.   8 × 8

C.   3 × 8

D.   8 × 3

E.   3 + 3 + 3

F.   8 + 8 + 8

Target Task - Problem 2

Find the side length of the rectangle below.

Fishtank Learning curriculum image

Word Problem

During a school fundraiser, Habib sells 8 half-year magazine subscriptions of 6 magazines each. Habib sold 27 fewer magazines than Habib. How many magazines did Ebru sell?