Question

The 17th term of an AP exceeds its 10th term by 21. find common difference​

Answer 1

Answer:

The common difference of the AP is..

(T17-T10)=21

⇒(a+16d)-(a+9d)=21

⇒7d=21

⇒d=3.

Answer 2

Answer:

Step-by-step explanation:

Here,

T₁₇ = a+16d, ----------(1)

T₁₀ = a+9d, -----------(2)

And, T₁₇ = T₁₀ + 21 ---------(3)

So, by transposing (3)

T₁₇ - T₁₀ = 21,

Now plugging in the values from (1) and (2);

(a+16d)-(a+9d) = 21

=> a+16d-a-9d = 21

=> 7d = 21

=> d = 21/7

=> d = 3

Hope it helps....