1. Mental Multiplications
Grouping Numbers in
Mental Multiplications
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2. 2 x 53 x 5 = 10
x 53 =
530
2 x 19 x 5 = 10
x 19 =
190
2 x 13 x 50 =
100
x 13 =
1300
4 x 43 x 25 =
100
x 43 =
4300
2 x 9 x 2.5 = 5
x 9 = 45
4 x 77 x 2.5 = 10
x 77 =
770
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3. 4 x 91 x 25 =
100
x 91 =
9100
2 x 17 x 50 =
100
x 17 =
1700
4 x 33 x 25 =
100
x 33 =
3300
2 x 11 x 500 =
1000
x 11 =
11000
4 x 16 x 25 =
100
x 16 =
1600
4 x 26 x 250 =
1000
x 26 =
26000
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4. 8 x 9 x 125 =
1000
x 9 =
9000
8 x 2 x 125 =
1000
x 2 =
2000
8 x 43 x 125 =
1000
x 43 =
43000
8 x 12 x 12.5 =
100
x 12 =
1200
8 x 36 x 1.25 = 10
x 36 =
360
4 x 7 x 125 =
500
x 7 =
3500
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5. 6 x 9 x 5 = 30
x 9 =
270
5 x 7 x 8 = 40
x 7 =
280
4 x 12 x 5 = 20
x 12 =
240
5 x 12 x 6 = 30
x 12 =
360
12 x 9 x 5 = 60
x 9 =
540
5 x 3 x 16 = 80
x 3 =
240
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6. © T Madas

7. 2 x 78 x 0.5 = 1
x 78 = 78
20 x 89 x 0.5 = 10
x 89 =
890
40 x 37 x 0.25 = 10
x 37 =
370
50 x 4.3 x 0.2 = 10
x 4.3 = 43
500 x 9.4 x 0.2 =
100
x 9.4 =
940
500 x 9 x 0.02 = 10
x 9 = 90
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8. 4 x 71 x 2.5 = 10
x 71 =
710
0.2 x 1.7 x 50 = 10
x 1.7 = 17
0.4 x 63 x 25 = 10
x 63 =
630
0.2 x 1.1 x 500 =
100
x 1.1 =
110
4 x 56 x 0.25 = 1
x 56 = 56
0.4 x 75 x 250 =
100
x 75 =
7500
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9. 8 x 0.2 x 125 =
1000
x 0.2 =
200
8 x 39 x 1.25 = 10
x 39 =
390
8 x 4.3 x 12.5 =
100
x 4.3 =
430
0.8 x 42 x 125 =
100
x 42 =
4200
0.8 x 66 x 1.25 = 1
x 66 = 66
0.8 x 0.7 x 1250 =
1000
x 0.7 =
700
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10. 6 x 0.9 x 5 = 30
x 0.9 = 27
5 x 1.1 x 0.8 = 4
x 1.1 =
4.4
0.4 x 32 x 5 = 2
x 32 = 64
5 x 7.5 x 0.6 = 3
x 7.5 =
22.5
1.2 x 0.7 x 5 = 6
x 0.7 =
4.2
5 x 0.15 x 1.6 = 8
x 0.15 =
1.2
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11. © T Madas