Question

4. In an A.P first two terms are 5 and 8 then 15th term is…

a) 123 b) 143 c) 137 d) 117​

Answer 1

Given,

The first two terms of the AP = 5 and 8

To find,

The 15th term of the given AP.

Solution,

We can easily solve this mathematical problem by using the following mathematical formula.

nth term of an AP = a + (n-1) × d

Here,

a = first term of AP

n = number position of the necessary term

d = common difference

Now,

common difference (d) = Second term - First term

= 8-5

= 3

By putting the values we get that,

15th term of the AP = 5 + (15-1) × 3 = 5+14×3 = 47

Hence, the 15th term of the given AP is 47.