If the first term of an A .P . is 3 and the sum of its first 25 terms is equal to the sum of its next 15 terms, then the common difference of this A .P . is:

Question

Accepted Answer

Correct answer: A. (a)JEE Main 2020 Here a=3 \&s_25=s_15^1 ⇒2s_25=s_40 ⇒2 252 [6+24d ]= 402 [6+39d ] ⇒25 [6+24d ]=20 [6+39d ] ⇒150+600d=120+780d ⇒180d=30 ⇒d= 16

$If the first term of an A . P . is 3 and the sum of its first 25 terms is equal to the sum of its next 15 terms, then the common difference of this A . P . is:$

Solution

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