__Question 3__Given an arithmetic progression

*p*+ 9, 2

*p*+ 10, 7

*p*– 1,…., where

*p*is a constant. Find

(a) the value of

*p*,

(b) the sum of the next five terms.

**[ Remember :**

**If a, b , c are three consecutive term of arithmetic progression, then c – b = b – a ]**

**Solution:**

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