If all multiples of 3 and all multiples of 4 are removed from the list of whole numbers 1 through 100, then how many whole numbers are left?
let U be the set of whole numbers 1−100and let V be U with the multiples of 3 and 4 removed|V|=|U|−|multiples of 3 < 100|−|multiples of 4≤100|+|multiples of both 3 and 4≤100|
|U|=100|multiples of 3<100|=33|multiples of 4≤100|=25|multiples of 3 and 4≤100|=|multiples of 12≤100|=8|V|=100−33−25+8=50
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