Mental Math
Rounding whole numbers and decimals
Estimating Sums and Differences
Adding Decimals
Subtracting decimals
100
1.9 + 3.4=
What is 5.3
100
To round 7,458 to the nearest hundred, which digit do you look at? What is 7,458 rounded to the nearest hundred?
What is five and 7,500
100
Estimate the sum 87.2 + 3.9
What is 87 + 4 = 91
100
Find the sum 45.09+ 2.005=
What is 47.095 $10 bonus if you can tell me the place value the five is in
100
Find the difference $43.80-$16.00=
What is $27.80
200
Being able to add two or more decimals in any order is an example of
What is the commutative property
200
23.009 Round each number to the place of the underlined digit.
What is 23.01
200
Estimate the difference $3,856 - $2,357 =
What is $4,000 - $2,000 = $2,000
200
Find the sum 9.001+1.999
What is 11.0
200
Find the difference 65.29 - 28.038
What is 37.252
300
Round 123,456 to the nearest thousand
What is 123,000
300
The world's largest aloha shirt measures 4.26 meters around the chest. Round 4.26 to the nearest ONES and to the nearest TENTH place.
What is 4 4.3
300
Tony cycled 14 miles each day on Saturday and Monday and 13 miles each day on Tuesday and Thursday. How many miles did she cycle in all?
What is 14+14+13+13= 54 or 14x2= 28 13x2= 26 28+26= 54
300
A balloon mural of the Chicago skyline measures 17.6m on two sides and 26.21m on the other two sides. What is the perimeter of the mural?
What is 87.62m
300
Find the difference 34.49 - 12.619
What is 21.871
400
Tony buys 12 apples at $1 each. He uses a coupon for $1.50 off. How much did Tony spend on his apples?
What is $10.50
400
In the first three quarters of a basketball game, a team scored 17, 25, and 13 points. Their final score was 75. How many points did the team score in the fourth quarter?
What is 17 + 25 + 13= 55 75 - 55 = 20
400
On vacation Trey spent $13 each day on Monday and Tuesday. He spent $9 each day on Wednesday and Thursday. If Trey brought $56 to spend, how much money did he have left to spend?
What is 13x2= 26 9x2= 18 26+18 =44 56-44= $12
400
Maria spent $7.99 on a book and $12.75 on art supplies. Hoe much did she spend altogether on the book and art supplies?
What is $20.74
400
Find the difference 7.094 - 3.657=
What is 3.437
500
7.03 + 9.0 + 3.07 =
What is 19.1
500
Round this number to the nearest HUNDRED THOUSAND 15,659,999
What is 15,700,000
500
Estimate 74.05 + 9.72 + 45.49 by rounding to the nearest whole number. What numbers did you add?
What is 74+10+45= 129
500
At a flower shop, Stephanie sees that liles are $3 each, carnations are $4 for three flowers, and tulips are $4 for four. She has $20. How much change does Stephanie get back?
What is $7
500
An average person's femur measures 19.88 inches and their tibia and fibula meadure 16.94 inches. How much longer is their upper bone than the lower leg bone?
What is 2.94 inches