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Weekly Problem 1 - 2009

Stage: 3 Short Challenge Level: Challenge Level:2 Challenge Level:2

Every second meal I will have soup for my starter.
Every $5$th meal I will have meat for my main course.
Every $3$rd meal I will have crumble for my afters.

$2, 5$, and $3$ have no common factors, so I will have eaten $2\times5\times3=30$ school dinners before I sit down to the same combination.

This problem is taken from the UKMT Mathematical Challenges.

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