__Question 11__An arithmetic progression consists of 10 terms. The sum of the last 5 terms is 5 and the fourth term is 9. Find the sum of this progression.

*[ Hint : You can find the sum of the first five terms using*

*(a) Sn formula using S 5 : S n = n 2 [2a+(n−1)d]*

*(b) Tn formula where S 5 = T 1 + T 2 + T 3 + T 4 + T 5]*

**Solution:**