Rounding
Mental Math
Round and Multiply
100

85 rounds to

90

100

20 x 20

400

100

23 x 7

20 x 7 = 140

200

32 rounds to

30

200

300 x 50

15,000

200

37 x 6

40 x 6 = 240

300

65 rounds to 

70

300

600 x 30

18,000

300

25 x 8

30 x 8 = 240

400

25 rounds to 

30

400

400 x 400

160,000

400

44 x 7

40 x 7 =280

500

99 rounds to

100

500

70 x 400

28,000

500

79 x 6

80 x 6 =480