Lesson 23 Divide Whole Numbers by Decimals

- Let’s divide whole numbers by decimals.

Warm-up True or False: Tenths and Hundredths

Decide if each statement is true or false. Be prepared to explain your reasoning.

$6 \div 0.01 = 60$
$6 \div 0.1 < 6 \div 0.01$
$6 \div 0.01 = 60 \div 0.1$

Activity 1 Same Divisor, Different Dividend

Problem 1

Find the value of each expression. Explain or show your reasoning.

$1 \div 0.2$
$2 \div 0.2$
$3 \div 0.2$
$4 \div 0.2$

Problem 2

Find the value of each expression. Explain or show your reasoning.

$1 \div 0.02$
$2 \div 0.02$
$3 \div 0.02$
$4 \div 0.02$

Problem 3

What patterns do you notice?

Activity 2 Evaluate Expressions

Problem 1

Find the value of the expression. Use a diagram if it is helpful.
$12 \div 0.2$
This is the diagram and explanation Tyler used to justify why $12 \div 0.2 = 60$ .

Explain how the expression $12 \times (1 \div 0.2)$ relates to Tyler’s reasoning.

Problem 2

Find the value of each expression.

$14 \div 0.5$
$5 \div 0.25$

Practice Problems

Problem 1

Find the value of $2 \div 0.2$ . Use the diagram if it is helpful.
Find the value of $21 \div 0.2$ .

Problem 2

Here is a diagram.

Two diagrams. Each squares.

Explain or show how the diagram shows $200 \div 25$ . What is the value of the expression?
Explain or show how the diagram shows $2 \div 0.25$ . What is the value of the expression?