Mental Math
Adding without Regrouping
Adding with Regrouping
Real World Problems
100

Find the sum of 80 and 57.

137

100

54+12

66

100

99 + 88

187

100

    Jade    had    1,458    paper    clips.     She    had    396    fewer    paper    clips    than    Pedro. a     How    many    paper    clips    did    Pedro    have?

Pedro had 1,854 paper clips.

200

Find the sum of 54 and 92.

146

200

567 + 2,102

2,669

200

579 + 879

1,458

200

A    shop    sold    2,390    bottles    of    water    on    Saturday.         350    more    bottles    were    sold    on    Sunday    than    on    Saturday. How    many    bottles    of    water    were    sold    on    Sunday?

2,740 bottles of water were sold on Sunday

300

Find the sum of 435 and 75.

510

300

43 + ___ = 98

55

300

4,563 + 9,789 

14,352

300

There are 5,740 visitors at Exhibition A. There are    2,871 visitors at Exhibition B. Another 1,388 visitors    arrive at Exhibition B. How many visitors are there    at Exhibition B now?

 There are 4,259 visitors at Exhibition B now

400

Find the sum of 58 and 192.

...then add 10.

260

400

Find each missing digit: A5B + BA2 = 786

A=3

B=4

400

Identify the mistake: 384 + 443 = 727

827

400

Ms. Lopez had some money. She spent half of her money and gave $300 to her mother. If Ms. Lopez had $1,878 left, how much money did she have at first?

She had $4,356 at first.

500

Find the sum of 83 and 57.

...then add 25. What is the final sum?

160

500

Find each missing digit: 7,AB2 + 24B = 7,B97

A=3

B=5

500

Identify the mistake: 184 + 460 = 544

644

500

There are 3,422 fiction books, 1,451 non-fiction books, and 595 audiobooks in Fairmount Library. Estimate the total number of books in the library by rounding to the nearest hundred.

About 5,500