Rounding by Compatible Numbers

Estimate 53.87 - 3.56 by rounding with compatible numbers.

• 54 - 4 = 50

• 55 - 3 = 52

• 50 - 5 = 45

CHALLENGE QUESTION

• A

• B

• C

• D

Estimate 29.34 x 2.843 by rounding with compatible numbers.

• 29 x 3 = 87

• 30 x 3 = 90

• 30 x 2 = 60

Estimate 30.8 divided by 4.96 by rounding with compatible numbers.

• 32 divided by 4 = 8

• 30 divided by 6 = 5

• 30 divided by 5 = 6

Which is the best estimate of 104 × 7 by using rounding or compatible numbers?

• 70

• 500

• 620

• 700

Which is the BEST estimate of 6 × 22 by using rounding or compatible numbers?

• 100

• 120

• 150

• 180

Which is the best estimate of 23 × 52 by using rounding or compatible numbers?

• 100

• 1,000

• 10,000

• 100,000