Composing 30

Discrete Mathematics Level 3

How many ways can the number \(30\) be written as an ordered sum of 2s and 5s?

Details and assumptions

There are four ways to write 12 as an ordered sum: \(2+2+2+2+2+2=12,\) \(2 + 5 + 5 = 12,\) \(5 + 2 + 5 = 12\), and \( 2 + 5 + 5 = 12 \). The ordered sum can use 0 5's, and it can also use 0 2's.

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