Find 'n' and Sn in an A.P. where a=5, d = 3 and an= 50.
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Answer:
n=16, Sn=440
Step-by-step explanation:
a=5, d=3, An=50
An=a+(n-1)d
50=5+(n-1)3
50=5+3n-3
50=5-3+3n
50=2+3n
3n=50-2
3n=48
n=48/3
n=16
Sn=n/2(a+An)
Sn=16/2(5+50)
Sn=8(55)
Sn=440
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