Estimating Tac

When you see the words "estimate" or "about" in a word problem, what do you have to do?

• regroup

• round

estimate: 86-22=

• 70

• 64

estimate: 482-161=

• 300

• 400

estimate: 617-123=

• 500

• 400

Which is good estimate for 47 x 23

• 50x30= 1,500

• 40x30= 1,200

• 40x20= 800

• 50x20= 1,000

Jenny is estimating the product of 29 x 66. She rounds the factors to 30 x 70 and gets a product of 2,100. Is that true or false?

• true

• false

ESTIMATE the product: 532 x 37

• 500 x 30 = 1,500

• 500 x 40 = 2,000

• 500 x 40 = 20,000

• 600 x 40 = 24,000

Place the rounded factor in the right place.

• 30,000 x 400

• 89 tens x 63 tens

• 3000 x 40

• 28,090 x 420

• 9,000 x 60

• 398 hundreds x 52 tens

• 900 x 600

• 8,932 x 59

• 400,000 x 50

• 2,809 x 42

ESTIMATE the PRODUCT
99 X 7=

• 70

• 700

• 7,000

• 7

Estimate the product: 243 x 33

• 200 x 30 = 6,000

• 300 x 30 = 900

• 300 x 40 = 12,000

• 200 x 40 = 8,000