Addition and Subtraction of Decimals Review

What is the best estimate for the answer to 
7.82 + 31.23

• 30
• 39
• 0.39
• 100

What is the best estimate for the difference of 
33 - 10.23

• 10
• 200
• 23
• 9

Add.
5.37 + 16.45

• 21.82
• 70.15
• 21
• 16.987

Add. 
7 + 5.826

• 5.833
• 6.526
• 75.826
• 12.826

Add.
-5.62 + (-12.9)

• 18.52
• -18.52
• -17.52
• 6.91

Subtract. 
7.89 - 5.91

• 2.02
• 2.08
• 1.98
• 1.88

Subtract.
17 - 4.12

• 2.32
• 4.05
• 13.12
• 12.88

Subtract. 
9.85 - 41

• -31.15
• 31.15
• 9.43
• -50.85

Angela runs her first lap around the track in 4.35 minutes, her second lap in 3.9 minutes and her third lap in 5.102 minutes.  What was her total time for the three laps?

• 5.576 min
• 8.25 min
• 13 min
• 13.352 min

A jeweler has 122.83 grams of silver.  He uses 45.7 grams of the silver to make a necklace and earrings.  How much silver does he have left?

• 168.53 g
• 77.13 g
• 118.26 g
• 87.13 g