Question

Which term of the A.P is4,9,14 19...., is 124?

Answer 1

Heya!!

The A.P is :

4,9,14,19,.......

Then,

a = 4

d = a2 - a1 = 9 - 4 = 5

a(n) = 124

By general term,

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

=) 124 = 4 + (n-1)5

=) 124 - 4 = (n-1)5

=) 120 = (n-1)5

=) 120/5 = n-1

=) 24 = n - 1

=) n = 25

Hence, 25th of this AP is 124.

Hope it helps uh :)

Answer 2

nth term =a+(n-1)d,a=first term,n=nth term d=common difference
124=4+(n-1)5
124=4+5n-5
124=-1+5n
125=5n
n=25
124 is the 25th term.