Question

the first term of ap is 5 and nth term is 17 and sum of all these terms are 275​

Answer 1

S = n/2×(2a+(n-1)d

275=17/2×(2×5+(17-1)d

275×2=17×(10+16d)

550=17(10+16d)

550/17=10+16d

32.35=10+16d

32.35-10=16d

22.35=16d

22.35/16=d

1.39=d

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