Adding and subtracting decimal numbers

Chris ran a race in 13.2 minutes. George ran a race in 13.54 minutes. What is the sum of their running times, rounded to the nearest tenth?

• 26.74

• 26.70

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.B.4

CCSS.5.NBT.B.7

Estimate to the nearest PLACE VALUE and solve:

947.4 − 462.7

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.B.4

CCSS.5.NBT.B.7

Estimate the sum of the expression 4.91 + 15.04 to the nearest integer.

• 21

• 19

• 20

• -20

• 18

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.B.4

CCSS.5.NBT.B.7

Choose a good pair of compatible numbers to make finding the sum of 223.4 + 148.9 easier to add mentally.

• 200 + 100

• 223 + 149

• 225 + 150

• They're already compatible.

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.B.4

CCSS.5.NBT.B.7

What is a reasonable estimate of the sum of 2.25 and 1.23?

• 7

• 0.5

• 3

• 16.00

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.B.4

CCSS.5.NBT.B.7

Round to the nearest WHOLE number to find the sum:

44.56 + 14.72

• 59.28

• 50

• 60

• 58

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.B.4

CCSS.5.NBT.B.7

Estimate the sum:

58.321 + 67.043

• 9

• 125.364

• 200

• 125

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.B.4

CCSS.5.NBT.B.7

Estimate the sum by rounding each number to the nearest whole number and then adding.

10.17 + 5.13 + 2.6

The sum is approximately

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.B.4

CCSS.5.NBT.B.7

Estimate the SUM:
9.1 + 7.9

• 15
• 17
• 18
• 2

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.B.4

CCSS.5.NBT.B.7

Wesley estimated 5.82 - 4.21 to be about 2. Is this an overestimate or an underestimate?

• overestimate

• underestimate

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.B.4

CCSS.5.NBT.B.7