SOLUTION: Find the sum of all the integers divisible by 7 between 32 and 5000. a) 1,514,285 b) 1,515,285 c) 1,615,185 d) 1,786,715 e) none of these

Algebra ->  Divisibility and Prime Numbers -> SOLUTION: Find the sum of all the integers divisible by 7 between 32 and 5000. a) 1,514,285 b) 1,515,285 c) 1,615,185 d) 1,786,715 e) none of these      Log On


   

Question 251681: Find the sum of all the integers divisible by 7 between 32 and 5000.
a) 1,514,285 b) 1,515,285 c) 1,615,185 d) 1,786,715 e) none of these
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find the sum of all the integers divisible by 7 between 32 and 5000.
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It would be an arithmetic series with:
a(1) = 35 = 5*7
a(n) = 4998 = 714*7
So n = (714-5)+1 = 710
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Formula: S(n) = (n/2)(a(1)+a(n))
S(708) = (710/2)(35 + 4998) = 1,786,715
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Cheers,
Stan H.
a) 1,514,285 b) 1,515,285 c) 1,615,185 d) 1,786,715 e) none of these
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