Question

Find the sum of first 22 terms of an A.P. in which d = 22 and a₂₂ = 149.

Answer 1

In the given problem, we need to find the sum of first 22 terms of an A.P. Let us take the first term as a.

Here, we are given that,

Also, we know,

For the 22^nd term (n = 22),

So, as we know the formula for the sum of n terms of an A.P. is given by,

Where; a = first term for the given A.P.

d = common difference of the given A.P.

n = number of terms

So, using the formula for n = 22, we get,

Therefore, the sum of first 22 terms for the given A.P. is.