The sum of 10 successive numbers is 155, then the average of the number(s) in middle is?

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22 Feb 2010 Average of middle number?

The sum of 10 successive numbers is 155, then the average of the number(s) in middle is?

OPtion

1) 15
2) 11.5
3) 16
4) 16.5
5) 15.5
6) 17
7) 18.5
8) 20
9) 10.5
10) 12.5

Solution

We know that the sum of first 10 integer starting from 1 is 55,
On increasing every integer by 10 we can obtain a sum of 155
Middles are 15 and 16, hence average is 15.5

Correct Option: 5 Best Solution (3)