Rounding and Estimation for Addition and Subtraction

Estimate the sum of: 68 + 52

• 200

• 100

• 50

the sum using front-end estimation =

• 50

• 60

• 40

Using rounding strategy

• 300

• 500

• 400

Estimate the sum using rounding strategy

• 200+500=700

• 100+500=600

• 200+600=800

Estimate the number using front-end estimation

• 40

• 30

• 50

Estimate the number 86 using the rounding strategy

• 80

• 90

• 100