Q. 223.8( 5 Votes )

# If the 12th term of an A.P. is - 13 and the sum of the first 4 terms is 24, what is the sum of the first 10 terms?

Answer :

assuming an AP whose first term is a and the common difference is d

**To find**: the sum of first 10 terms

**Given** 12^{th} term is - 13

So, a + 11d = - 13...(i)

**Given** the sum of first four terms is 24

So 4a + 6d = 24…(ii)

Solving (i) and (ii) we get

a = 9 and d = - 2

we know that the sum of AP is given by the **formula:**

substituting the values in the above equation

s = 0

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