Question

which term of an A.P. 70, 63, 56, 49... is 21 ?

Answer 1

Given:-

• A.P. are is in the 70, 63, 56, 49......
• Last term = 21
• First term = 70
• Common difference= (70-63) = -7

To find:-

• Which term of the given A.P. is 21 = ?

Find:-

Let the first term be a and common difference be d and last term be l.

First term(a) = 70

Common difference(d) = (70-63)= -7

We know that,

L = a + (n-1)d

=>21= 70 + (n-1)(-7)

=>21 = 70 -7n+7

=>21 = 77- 7n

=>7n= 77-21

=>7n = 56

=>n = 8

Hence its 8th term will be 21.

Hope its help uh❤

Answer 2

Answer:

8th term will be 21.......