Finding Sums and Differences with Mental Math
Estimate Sums and Differences
Add Whole Numbers
Add Greater Numbers
Subtract Whole Numbers
100

Use mental math strategies to solve:

6,794 - 999

5,795

100

Estimate each sum or difference:

5,638 + 3,753

9,400 (Answers may vary)

100

148 + 157

305

100

14,312 + 9,617

23,929

100

154 - 89

65

200

Use mental math strategies to solve:

4,505 + 3,515

8,020

200

Estimate each sum or difference:

63,526 + 25,038

89,000 (Answers may vary)

200

389 + 461

850

200

275,558 + 605,131

880,689

200

592 - 357

235

300

Use mental math strategies to solve:

9,100 + 2,130 + 900

12,130

300

Estimate each sum or difference:

262,262 - 132,147

130,000

300

565 + 694

1,259

300

5,555 + 7,412

12,967

300

915 - 288

627

400

Use mental math to solve:

8,375 + 31,145

39,520

400

Estimate each sum or difference:

5,323 + 2,611

8,000 (Answers may vary)

400

375 + 548

923

400

21,009 + 5,529

26,538

400

743 - 694

49

500

Use mental math to solve:

6,686 - 1,443

5,243

500

Estimate each sum or difference:

49,761 + 59,499

110,000 (Answers may vary)

500

909 + 624

1,533

500

64,673 + 48,262 + 8,918

121,853

500

525 - 267

258