Question

Find n if the given value of x is the nth term of the given A.P.

25, 50, 75, 100, ...; x = 1000

Answer 1

In the given problem, we need to find the number of terms in an A.P

25, 50, 75, 100 …

We are given,

`a_n = 1000`

Let us take the total number of terms as n

So,

First term (a) = 25

Last term (`a_n`) = 1000

Common difference (d) = 50 - 25

= 25

Now as we known

`a_n = a + (n - 1)d`

So for the last term

1000 = 25 + (n - 1)25

1000 = 25 + 25n - 25

1000 = 25n

`n = 1000/25`

n = 40

Therefore, the total number of terms of the given A.P. is `n = 40`