Unit 2 Review

Mental Math (estmating )

100

7,000 - 827

Estimate the difference

6,200

200

1,225 + 975

Estimate the sum

2,200

300

5491 + 2860

Estimate the sum

84,000

400

6686 - 1443

Estimate the difference

5,300

500

31,145 + 8,375

Estimate the sum

39,500

Sums ( addition )

100

148 + 157

305

200

1,234 + 675

1,909

300

23,508 + 5,132

28,640

400

45,629 + 21,987

67,616

500

56,932 + 55,143

112,075

Difference ( subtraction )

100

289 - 145

144

200

5647 - 467

5,180

300

86,432 - 7,192

79,240

400

87,432 - 21,671

65,761

500

987,643 92,194

895,449

Estimate Sum/ Difference

100

Estimate the SUM

23 + 47

70

200

Estimate the DIFFERENCE

76 - 34

50

300

Estimate the SUM

831 - 365

400

400

Estimate the SUM

972 + 749

1,700

500

Estimate the DIFFERENCE

3,256 - 822

2,500