Adding, Subtracting, Multiplying Decimals

What is the rule for adding or subtracting decimals?

• Add first

• Line up the numbers by place value

• Move the decimal to the right the total amount of numbers after the decimal.

• Subtract

5.4 + 0.5 =

• 4.5

• 4.9

• 5.9

• 5.8

7.2 - 4.3 =

• 2.9

• 3.9

• 3.1

• 2.1

Jim earns $22.50, $14.75, and $8.50 on three different days.  How much did he earn in all? 

• $28.75
• $45.25
• $45.75
• 457.50

2.612 x 4 =

• 1.0448
• 10.448
  10.448
• 8.448
• 84.48

9.7 - 3.2 =

• 6.5

• 12.9

• 65

• 1.29

5.6 + 4.2 =

• 9.6

• 9.8

• 9.2

• 1.4

0.265 x 7 = 

• 1.745
• 1.855
• 17.45
• 18.55

Reese is buying school supplies. He buys a notebook for $2.45, a package of pencils for $3.79, and an eraser for $1.55. How much did he spend in all? Find the sum.

• 0.21

• 4.69

• 6.24

• 7.79

6.70 - 2.33 =

• 4.43

• 4.4

• 4.37

• 4.47