Given a=5,d=3,an=50,find n and sn

1.	Given a=5,d=3,an=50,find n and sn
Answer» Given,\xa0a=5,d=3,an\u200b=50⇒a+(n−1)d=50⇒5+(n−1)3=50⇒5+3n−3=50⇒3n=48⇒n=16∴S16\u200b=16/2\u200b[2a+(16−1)d]=8[2×5+15×3]=440Hence,\xa0n=16,S16\u200b=440 añ=a+(n-1)d50=5+(n-1) 350=5+3n-350=2+3n50-2=3n48=3n48/3=n16=nSn=n/2(a+añ)Sn=16/2(5+50)Sn=8(55)Sn=440

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