Adding Decimals
Subtracting Decimals
Estimating Sum or Difference
Word Problems
100

3.512 + 7.201 = ?

10.713

100

5.562 - 3.420 = ?

2.142

100

What is a reasonable estimate for the sum of 9.865 and 4.307?

10 + 4 = 14

100

At the long-jump event, Autumn's first jump was 6.257 meters. Her second jump was 5.998 meters. How much longer was her first jump?

0.259 meter

200

Find the sum of 26.048 and 4.1

30.148

200

Find the difference between 6.258 and 4.340

1.918

200

What is a reasonable estimate for the difference of 8.325 and 5.9?

8 - 6 = 2

200

McKinley walked 2.38 miles yesterday. She walked 1.196 miles today. About how many miles did McKinley walk both days?

About 3 miles

300

What is the sum? Use an algorithm to solve.

 0.648 + 0.279 =

0.927

300

What is the difference? Use an algorithm to solve.

0.7 - 0.123 =

0.577

300

Sebastian rode his bike 3.254 miles on Wednesday and 1.87 miles on Thursday. About how many miles did he ride his bike total?

About 5 miles

300

Reagan and his father catch two fish. The first fish weighs 5.534 pounds. The second fish weighs 2.921 pounds. What is the combined weight of the two fish?

8.455 pounds

400

Which of the following is a correct way to find  

26.34 + 12.53? Choose all that apply.

A. 2 + 1 + 6 + 2 + 3 + 5 + 4 + 3

B. 2 + 1 + 6 + 2 + 0.3 + 0.5 + 0.4 + 0.3

C. 20 + 10 + 6 + 2 + 0.3 + 0.5 + 0.04 + 0.03

D. 26 + 12 + 0.34 + 0.53

C and D

400

What is the difference between 3.532 and 3.121?

0.411

400

Judah walked 1.744 miles yesterday. He walked 2.199 miles today. About how many miles did Judah walk both days?

About 4 miles

400

Khalil and his brother had dinner at their favorite restaurant. The total cost for their two entrees was $21.52. The cost of Khalil’s meal was $7.99. What was the cost of his brother’s meal?

His brother's meal cost $13.53

500

Find the sum of 765.022 and 113.789

878.811

500

Find the difference between 3 and 2.015

0.985

500

Where Brinley lives, the average high temperature in July is 87.46°F. The average low temperature in July is 64.82°F. Write an equation that estimates the difference between the average high and low temperatures in July.

Possible answers:

87 - 65 = 22

87.5 - 64.8 = 22.7

500

Deliza walked 6.42 miles yesterday. She walked 2.619 miles today. About how many miles did Deliza walk both days?

She walked about 9 miles total.