We have a question that asks to find the number of integers between 1 and 100 that are divisible by 2,3 or 5.(adsbygoogle = window.adsbygoogle || []).push({});

So i use the sum rule

let E,F and G be the the integers. so,

n(EUFUG) = n(E) + n(F) + n(G) - n(EnF) - n(EnG) - n(FnG)

but this doesn't work. it gives me the answer of 70 but the actual answer is 74. Since I know the answer is 74 this one doesn't matter but the next question asks to find the number of integers between 1 and 100000. So it's obvious that I cant count them.

just to make sure I did the above part right

n(EUFUG) would be 100/2 + 100/3 + 100/5 - 100/6 - 100/10 - 100/15 correct?

I hope somone can figure out where i've gone wrong.

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# Homework Help: Finding the integers

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