Question

if difference of 25th and 20th term of A.P. is 15 then find common difference.


plZ answer this....

Answer 1

Solution :

Let a , d are first term and common

difference of an A.P ,

According to the problem given ,

a25 - a20 = 15

=> a + 24d - ( a + 19d ) = 15

=> a + 24d - a - 19d = 15

=> 5d = 15

=> d = 15/5

=> d = 3

Therefore ,

Required common difference

= d = 3

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