# There are some consecutive even numbers and their average is 310, here the number of terms are odd. What will be the average of second and second last

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There are some consecutive even numbers and their average is 310, here the number of terms are odd. What will be the average of second and second last number?

1. 130
2. 310
3. 340
4. 379.2

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Correct Answer - Option 2 : 310

Given:

There are some consecutive even numbers and their average is 310

Concept Used:

When number of observations are odd, then average is same for first and last, second and second last, third and third last,……., so on.

Calculation:

From concept above, the average of second and second last number is 310 = Average of all numbers

Example:

2, 4, 6, 8, 10, 12, 14

Total terms are odd, average of terms is 8

Sum of first and last = 2 + 14 = 16

Average of first and last = 16/2 = 8 = Average of all terms

Sum of second and second last terms = 4 + 12 = 16

Average of second and second last terms = 16/2 = 8 = Average of all terms

Similarly for third and third last term, average will be 16/2 = 8 = Average of all terms

This is applicable only when the terms are consecutive or the terms have same common difference. (If they are in AP)