<PRE><B>Question 935867</B>
The first and the last term of an arithmetic progression are 9 and 93.If the sum of the arithmetic progression is 663,find the number of terms.
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a = 9
a(n) = 9+(n-1)d = 93
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(n/2)(9+93) 663
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n*51 = 663
n = 13
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Ans:: n = 13
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Cheers,
Stan H.
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