Addition Estimation

Solve using an open number line

236 + 127 =

• A
• B
• C
• D

You know your answer is reasonable if _______________

• It is 100 away from your estimate

• it is close to your estimate

• if it is far away from your estimate

• if it is in a ballpark

Cale bought 231 cows and Lisa bought 392 cows. About how many total cows did they buy?

• 600 cows

• 500 cows

• 200 cows

• 100 cows

360 + 490

• 400 + 500 = 900

• 300 + 400 = 700

• 320 + 600 = 920

• 200 + 700 = 900

Round to the nearest ten to estimate 546 + 53.

• 600 + 50 = 650

• 550 + 50 = 600

• 500 + 60 = 560

• 550 + 100 = 650

Add:  27 + 34 = ?

• 64

• 51

• 57

• 61

Oliver made 263 baskets at basketball practice last week. He made 312 baskets at practice this week. How many total baskets did Oliver make?

• 565 baskets

• 555 baskets

• 585 baskets

• 575 baskets

Add: 48 + 35 = ?

• 72

• 83

• 75

• 85

Estimate the answer:

906 + 397

• 1300

• 1200

• 1310

• 1303