Question

4 AP 21, 18, 15 which term is minus 27?

Answer 1

Given:

a=21

d=18-21=-3

n th term is a+(n-1)d

a+(n-1)d = -27

==> 21+(-3)(n-1)=-27

==>21-3n+3=-27

==>-3n=-27-24

==>-3n=-51

==>n=-51/-3

==>17

The 17th term is -27

Hope it helps

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