SOLUTION: The sum of the first 50 elements of a set is 6925 with a common difference of 5. What is the first element of the set.

Question 996734: The sum of the first 50 elements of a set is 6925 with a common difference of 5. What is the first element of the set.

Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
The sum of the first 50 elements of a set is 6925 with a common difference of 5. What is the first element of the set.
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S(n) = (n/2)(a(1)+a(n))
a(n) = a(1)+(n-1)d
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Solve for a(1)::
25(a(1)+[a(1)+49*5]) = 6925
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2*a(1) + 245 = 277
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2a(1) = 32
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a(1) = 16
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Cheers,
Stan H.
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