Question

The sum of first 15 terms of an arithmetic progression is 465 and the sum of first 14 terms of the same arithmetic progression is 406. Then its 15th term is​

Answer 1

Step-by-step explanation:

S15-S14=465-406

=59

please like and vote

Answer 2

Given :- The sum of first 15 terms of an arithmetic progression is 465 and the sum of first 14 terms of the same arithmetic progression is 406. Then its 15th term is ?

Solution :-

Let us assume that, the terms in AP series are A1, A2, A3, ______A15 .

so,

→ A1 + A2 + A3 + __________ + A15 = 465 ------ Eqn.(1)

and,

→ A1 + A2 + A3 + ___________ A14 = 406 ------ Eqn.(2)

so, subtracting Eqn.(2) from Eqn.(1)

→ (A1 + A2 + A3 + __________ + A15) - (A1 + A2 + A3 + ___________ A14) = 465 - 406

→ (A1 - A1) + (A2 - A2) + __________ (A14 - A14) + A15 = 59

then,

→ A15 = 59 (Ans.)

Or,

→ S(15) - S(14) = A(15)

→ 465 - 406 = 59 (Ans.)

Learn more :-

evaluate the expression given by 83 - 81 + 87 - 85 +__________ + 395 - 393 + 399 - 397

https://brainly.in/question/14081691

If the nth term of an AP is (2n+5),the sum of first10 terms is

https://brainly.in/question/23676839