Dividing Decimals

Dividing Decimals

A Complete Lesson

In this lesson, you will learn:

✓ How to divide a decimal by a whole number

✓ How to add zeros when there's a remainder

✓ How to divide a decimal by another decimal

Let's Get Started!

Standards Alignment

CCSS.MATH.5.NBT.B.7: Add, subtract, multiply, and divide decimals to hundredths

Grade Level: 5-6

Key Focus:

• Understanding place value with decimals

• Long division with decimals

• Making connections to whole number division

Key Vocabulary

Dividend: The number being divided (inside the bracket)

Divisor: The number we divide by (outside, to the left)

Quotient: The answer to a division problem

Remainder: What's left over after division

The Decimal Point Rule

Key Rule:

The decimal point in the quotient goes DIRECTLY ABOVE the decimal point in the dividend.

Example: When dividing 9.36 ÷ 4, the decimal in the answer (2.34) is directly above the decimal in 9.36

Section 1: Decimal ÷ Whole Number

Problem 1 (I Do): 9.36 ÷ 4

2
.
3
4
4
9
.
3
6
−
8
1
↓3
−
1
2
1
↓6
−
1
6
0

Answer: 2.34

Step 1 of N

Section 1: Decimal ÷ Whole Number

Problem 2 (I Do): 303.5 ÷ 5

6
0
.
7
5
3
0
3
.
5
−
0
3
↓0
−
3
0
0
↓3
−
0
3
↓5
−
3
5
0

Answer: 60.7

Step 1 of N

Section 1: Decimal ÷ Whole Number

Problem 3 (We Do): 50.85 ÷ 9

5
.
6
5
9
5
0
.
8
5
−
0
5
↓0
−
4
5
5
↓8
−
5
4
4
↓5
−
4
5
0

Answer: 5.65

Step 1 of N

Section 1: Decimal ÷ Whole Number

Problem 4 (We Do): 725.07 ÷ 3

2
4
1
.
6
9
3
7
2
5
.
0
7
−
6
1
↓2
−
1
2
0
↓5
−
3
2
↓0
−
1
8
2
↓7
−
2
7
0

Answer: 241.69

Step 1 of N

Section 1: Decimal ÷ Whole Number

Problem 5 (You Do): 7.68 ÷ 4

1
.
9
2
4
7
.
6
8
−
4
3
↓6
−
3
6
0
↓8
−
8
0

Answer: 1.92

Step 1 of N

Section 1: Decimal ÷ Whole Number

Problem 6 (You Do): 156.5 ÷ 5

3
1
.
3
5
1
5
6
.
5
−
0
1
↓5
−
1
5
0
↓6
−
5
1
↓5
−
1
5
0

Answer: 31.3

Step 1 of N

Section 2: Adding Zeros When There's a Remainder

Problem 7 (I Do): 7.23 ÷ 5

1
.
4
4
6
5
7
.
2
3
−
5
2
↓2
−
2
0
2
↓3
−
2
0
3

Answer: 1.446

Step 1 of N

Section 2: Adding Zeros When There's a Remainder

Problem 8 (I Do): 30.9 ÷ 4

7
.
7
2
5
4
3
0
.
9
−
0
3
↓0
−
2
8
2
↓9
−
2
8
1

Answer: 7.725

Step 1 of N

Section 2: Adding Zeros When There's a Remainder

Problem 9 (We Do): 6.27 ÷ 5

1
.
2
5
4
5
6
.
2
7
−
5
1
↓2
−
1
0
2
↓7
−
2
5
2

Answer: 1.254

Step 1 of N

Section 2: Adding Zeros When There's a Remainder

Problem 10 (We Do): 28.92 ÷ 8

3
.
6
1
5
8
2
8
.
9
2
−
0
2
↓8
−
2
4
4
↓9
−
4
8
1
↓2
−
8
4

Answer: 3.615

Step 1 of N

Section 2: Adding Zeros When There's a Remainder

Problem 11 (You Do): 9.45 ÷ 6

1
.
5
7
5
6
9
.
4
5
−
6
3
↓4
−
3
0
4
↓5
−
4
2
3

Answer: 1.575

Step 1 of N

Section 2: Adding Zeros When There's a Remainder

Problem 12 (You Do): 42.7 ÷ 4

1
0
.
6
7
5
4
4
2
.
7
−
4
0
↓2
−
0
2
↓7
−
2
4
3

Answer: 10.675

Step 1 of N

Section 3: Decimal ÷ Decimal

Problem 13 (I Do): 17.64 ÷ 1.4

× 10 both sides: 176.4 ÷ 14

Answer: 12.6

Step 1 of N
1
2
.
6
14
1
7
6
.
4
−
0
1
↓7
−
1
4
3
↓6
−
2
8
8
↓4
−
8
4
0

Section 3: Decimal ÷ Decimal

Problem 14 (I Do): 3.752 ÷ 0.05

× 100 both sides: 375.2 ÷ 5

Answer: 75.04

Step 1 of N
7
5
.
0
4
5
3
7
5
.
2
−
0
3
↓7
−
3
5
2
↓5
−
2
5
0
↓2
−
0
2

Section 3: Decimal ÷ Decimal

Problem 15 (We Do): 9.59 ÷ 0.7

× 10 both sides: 95.9 ÷ 7

Answer: 13.7

Step 1 of N
1
3
.
7
7
9
5
.
9
−
7
2
↓5
−
2
1
4
↓9
−
4
9
0

Section 3: Decimal ÷ Decimal

Problem 16 (We Do): 55.38 ÷ 1.3

× 10 both sides: 553.8 ÷ 13

Answer: 42.6

Step 1 of N
4
2
.
6
13
5
5
3
.
8
−
0
5
↓5
−
5
2
3
↓3
−
2
6
7
↓8
−
7
8
0

Section 3: Decimal ÷ Decimal

Problem 17 (You Do): 14.4 ÷ 0.8

× 10 both sides: 144 ÷ 8

Answer: 18

Step 1 of N
1
8
8
1
4
4
−
0
1
↓4
−
8
6
↓4
−
6
4
0

Section 3: Decimal ÷ Decimal

Problem 18 (You Do): 6.375 ÷ 0.25

× 100 both sides: 637.5 ÷ 25

Answer: 25.5

Step 1 of N
2
5
.
5
25
6
3
7
.
5
−
0
6
↓3
−
5
0
1
3
↓7
−
1
2
5
1
2
↓5
−
1
2
5
0

Summary

Section 1: Decimal ÷ Whole Number

Use long division, but keep the decimal point lined up!

Section 2: Adding Zeros

When you have a remainder, add zeros and keep dividing for more decimal places.

Section 3: Decimal ÷ Decimal

Multiply both by a power of 10 to make the divisor whole, then divide.

Great work! You've mastered dividing decimals!

Exit Ticket

Before you go, answer these:

1. How would you solve 4.2 ÷ 3?

2. What do you do when you get a remainder?

3. How do you divide by a decimal?

✓ Thank you for your hard work!

Slide 1 of 24 Dividing Decimals