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In the Hundreds

Stage: 4 Short Challenge Level: Challenge Level:1
See all short problems arranged by curriculum topic in the short problems collection

For how many positive values of $n$ are both $\frac{1}{2}n$ and $2n$ three-digit whole numbers?


If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.

This problem is taken from the UKMT Mathematical Challenges.