Question

The sum of all terms of the arithmetic progression having ten terms except for the first term, is 99, and except for the sixth term, 89. Find the third term of the progression if the sum of the first and the fifth term is equal to 10. 

(a) 15 

(b) 5 

(c) 8 

(d) 10

Answer 1

Correct option (b) 5

Explanation: 

Any sub-part of an AP is also an AP. Thus, the third term would be the average of the first and the fifth term. Hence, the third term would be 5.