Question

1. In an AP if the nth term is 55, n is 15 ans a=13 , then the common difference ​

Answer 1

Answer:

We know that the formula for the nth term is t

n

=a+(n−1)d, where a is the first term, d is the common difference.

It is given that the nth term is t

15

=55 and the first term is a=13, therefore,

t

n

=a+(n−1)d

⇒55=13+(15−1)d

⇒55=13+14d

⇒14d=55−13

⇒14d=42

⇒d=

14

42

=3

Hence, d=3

Answer 2

We know that the formula for the nth term is $t_n$

= a+(n−1)d, where a is the first term, d is the common difference.

It is given that the nth term is ,

$t_15$ =55 and the first term is a=13,

Therefore,

$t_n$=a+(n−1)d

⇒55=13+(15−1)d

⇒55=13+14d

⇒14d=55−13

⇒14d=42

⇒d=42/14

⇒d=3

Hence,

d=3