Question

I know the answer but please solve step by step and the isAnswer is D=2, s13=1155
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Answer 1

a=3

The formula for finding nth term in an AP: Tn = a + (n - 1) d

Given: a₁₆=33

∴3+ (16-1)d=33

15d=30

d=2

Sum of first n terms of an AP: S =(n/2)[2a + (n- 1)d]

S₁₃=(13/2)(2*3+12*2)

=13/2(30)

=195