1981 AHSME Problems/Problem 7

Problem 7

How many of the first one hundred positive integers are divisible by all of the numbers $2$, $3$, $4$, and $5$?

$\textbf{(A)}\ 0\qquad\textbf{(B)}\ 1\qquad\textbf{(C)}\ 2\qquad\textbf{(D)}\ 3\qquad\textbf{(E)}\ 4$

Solution

The least common multiple of $2$, $3$, $4$, and $5$ is $2^2 \cdot 3 \cdot 5 = 60$. There is only one multiple of $60$ between $1$ and $100$, so the answer is $\textbf{(B)}\ 1.$

-edited by coolmath34

See also

1981 AHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 6
Followed by
Problem 8
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All AHSME Problems and Solutions

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