Mental Madness
Estimating Experts
Adding Decimals
Subtracting Decimals
Word Problems
100

Use mental math to solve: 

12+3.4

What is 15.4

100

ESTIMATE:

179+277.1

What is 500
100

0.63+0.41

What is 1.04

100

16.82-5.21

What is 11.61

100

On three separate days, Mildred earned $27, $33, and $49. She wants to earn $100 for the new Labubu doll. If she buys the doll, how much money will she have left over?

What is $9

200

Use mental math to solve:

7.1+5.4

What is 12.5

200

ESTIMATE:

23.2-9.71

What is 13

200

2.02+0.8

What is 2.82

200

43.90-7.52

What is 36.38

200

ESTIMATE: Nico buys a video game for $7.89 and some new batteries for his controller for $5.49. If he pays the cashier $20, ABOUT how much change should he be expecting back?

What is $7

300

Use mental math to solve:

18.25+7.99+4.75

What is 30.99

300

ESTIMATE:

87.2+3.9

What is 91

300

10.22+0.34

What is 10.56

300

52.02-0.83

What is 51.19

300

DAILY DOUBLE!!!!!!!

Tluang earned $16 helping his mom wash the dishes and $17.50 mowing the lawn. He paid $8.50 for a movie and bought a small popcorn for him and his friend, Omar, for $1.95. How much money does Tluang have left?

What is $23.05

400

Use mental math to solve:

12+3.04+8.28

What is 23.32

400

ESTIMATE:

576+94.6

What is 700

400

271.90+34.22

What is 306.12

400

23.6-8.27

What is 15.33

400

Jake has $30.50. He wants to buy his dog a collar that costs $15, a toy that costs $3.79, and a matching leash that costs $14.79. How much more money does he need?

What is $3.08

500

Use mental math to solve:

9.04-6.98

What is 2.06

500

ESTIMATE:

837+488.12

What is 1,300

500

45.08+2.01

What is 47.09

500

8.04-0.3

What is 7.74

500

Leo is building a swing for his tree! He has a length of rope that is 32.7 meters long. He has another length of rope that is 15.33 meters long. How much longer is one rope from the other?

What is 17.37 meters

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