The average of 12 numbers is 8. If the average of first 11 of these numbers is 7, the twelfth number

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28 Oct 2021 AVERAGE

The average of 12 numbers is 8. If the average of first 11 of these numbers is 7, the twelfth number is:

OPtion

1. 22
2. 26
3. 12
4. 15
5. 17
6. 20
7. 18
8. 19
9. 16
10. None of the above

Solution

Sum of seven numbers = 12 × 8 = 96
Sum of first six numbers = 11 × 6 = 77
Therefore, the seventh number = 96 − 77 = 19

Correct Option: 8 Best Solution (3)