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Question
First guess the answer and then calculate:
382 × 3 = ?
Solution
On guessing this number will be near to 380 × 3 = 1140
On calculation:
| 300 | 80 | 2 | |
| 5 | 300 × 3 | 80 × 3 | 2 × 3 |
| 900 | 240 | 6 |
By adding the numbers in the last row you will get
900 + 240 + 6 = 1146
So, 382 × 3 = 1146.
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