The list 2, 1: 3, 2; 2,3; 1, 4; describes itself, since there are two 1s, three 2s, two 3s and one 4. There is exactly one other list of eight numbers containing only the numbers 1, 2, 3, and 4 that, in the same way, describes the numbers of 1s, 2s, 3s and 4s in that order.
What is the total number of 1s and 3s in this other list?
Select one option, then click Submit.
2
3
4
5
6
Select an option, then submit.
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Junior Mathematical Challenge 2008 (2008)
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