7th Grade Math

To divide by a decimal, multiply both the divisor and dividend by the

same power of ten so that the divisor is a whole number. Then divide.

divisor ) dividend

Divide Decimals

Find 199.68 ÷ 9.6. Estimate 200 ÷ 10 = 20

20.8

9.6  199.68 Move each decimal point one place to the right.

• 192
  768


• 768
  0 Check for Reasonableness 20.8 ≈ 20 

c. 9.81 ÷ 0.3 d. 5.76 ÷ 3.2

In many real-world situations, the remainder is not zero. So, the

quotient is usually rounded to a certain place-value position.

SPORTS Refer to the information on the previous page. Divide 200

by 19.3 to find Usain Bolt’s speed in meters per second. Round

your answer to the nearest tenth.

Estimate 200 ÷ 20 = 10

10.36

19.3  200.000 Move each decimal point one place to the right.

• 193
  7 0


• 0
  700


• 579
  1210


• 1158
  62
  Check for Reasonableness 10.4 ≈ 10 
  Usain Bolt’s speed is about 10.4 meters per second.

e. FOOD Mrs. Myers bought 2.5 pounds of hamburger for $5.20.

How much did she pay in dollars per pound?

Rounding

Look at the digit to the

right of the tenths place.

Since 6 is greater than 5,

10.36 is rounded to 10.4.

Lesson 3 Divide Decimals 11

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