19. If the sum of the first 14 teruus of an AP is 1050 aud its first t – InterviewSolution

1.

19. If the sum of the first 14 teruus of an AP is 1050 aud its first term is 10, find the 20th term.

Answer»

A=10...given

S14=1050⇒n/2[2a+(n-1)d]=1050⇒14/2[20+13d]=1050⇒7[20+13d]=1050⇒20+13d=1050/7⇒20+13d=150⇒13d=150-20⇒13d=130⇒d=10

20th term=a+19d =10+19×10 =10+190 =200...Answer

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