The 26th, 11th and the last terms of an AP are, 0, 3 and respectively.

Find the common difference and the number of terms.


Let the first term, common difference and number of terms of an AP are a, d and n, respectively.


Let the no of terms be x


By using the nth term formula i.e. an = a + (n - 1)d


a26 = a + 25d = 0 (given)


a = - 25d (eqn 1)


a11 = a + 10d = 3 (given)


- 25d + 10d = 3 (using eqn 1)


- 15d = 3


(eqn 2)


using eqn2 and eqn1 we get




Also,


(given)








hence


Common difference = - 1/5


No of terms = 27


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