Mental Math Addition with Decimals

To align decimal points in a decimal addition problem annex zeros to write ________ so that all addends have the same number of decimal places.

• equivalent decimals

• inverse operations

• associative property of addition

• commutative

Because the ______, I know that 477.75 + (76.89 + 196.25) = (76.89 + 196.25) + 477.75 without adding.

• Communative property of addition

• equivalent decimals

• inverse operations

• associative property of additoin

• 7050.06

• 7056

• 7050.6

• 70.56

Estimate the sum.

79.1 + 32.4 =

(remember to use your place value chart and line up the numbers)

• 80

• 90

• 35

• 110

Use mental math to find the sum:

23.85 + 16.15 + 7.42

Match the following equation to the correct answer.

• 11.57

• 3.9 + 8.2

• 12.1

• 7.58 + 4.6

• 12.18

• 0.65 + 10.92

• 11.57

• 5.57 + 6

What is the sum of 5.48 and 9.6?

Mathematical Equivalence

ON

5.61 + 2.4

Mathematical Equivalence

ON

Lia and James went to the movies. The tickets are $3.00 each.  Lia bought popcorn and a slushy for $8.50 together. James bought a slushy and nachos $12.00 together. How much money did they spend total?

• 26.50

• 2.650

• 3.00

• 53.65