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6. The last digit is 0. The digit after 0 is 3. Add 0 and 3. 0 + 3 = 3
This becomes the ten thousands digit of the answer.
TTh Th H T O
3 7 6 8 6
Thus, 3,426 × 11 = 37,686.
Quick Review
3 4 2 6 × 11 = 0 3 4 2 6 × 11 (Put 0 at the extreme left)
= 0 + 3 3 + 4 4 + 2 2 + 6 6 = 37,686
Example 13: 987 × 11 = ?
Solution: 987 × 11 = 0 9 8 7 × 11
= (0 + 9) (9 + 8) (8 + 7) 7
1
= 9 (17) (15) 7
= 9 (17 + 1) 5 7
1
= 9 (18) 5 7
= (9 + 1) 8 5 7
= 10 8 5 7 = 10,857
Thus, 987 × 11 = 10,857.
EXERCISE 5.8
1. Observe the following pattern and complete it.
1 × 9 + 2 = 11
12 × 9 + 3 = 111
123 × 9 + 4 = 1111
1234 × 9 + ___ = ___________
12345 × 9 + ___ = ___________
123456 × 9 + ___ = ___________
1234567 × 9 + ___ = ___________
12345678 × 9 + ___ = ___________
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