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Question
First guess the answer and then calculate:
142 × 5 = ?
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Solution
On guessing 142 × 5
The number will be near to 140 × 5 = 700
On calculation-
| 100 | 40 | 2 | |
| 5 | 100 × 5 | 40 × 5 | 2 × 5 |
| 500 | 200 | 10 |
By adding the numbers in the last row you will get
500 + 200 + 10 = 710
Hence, 142 × 5 = 710
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