Question

Which term of the A.P. 1, 4, 7, ..... is 88 ?​

Answer 1

Step-by-step explanation:

let An = 88

we know that,

An = a + (n-1)d

a = 1

d = 3

putting in formula

88 = 1 + (n - 1)3

87/3 = n - 1

n = 30

Answer 2

Which term of the A.P. 1, 4, 7, ..... is 88 ?

Solution:-

First term(a) = 1

common difference (d) = 3

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

88 = 1 + (n - 1)3

88 = 1 + 3n - 3

88 = 3n - 2

3n = 90

n = $\dfrac{90}{3}$

n = 30

________________________

†30th term of an AP is 88