



 
Hi, Try to list them in an orderly fashion. First of all what if all 5 digits are 5? There is only one item, 55555. Next, what if exactly 4 of the digits are 5? The remaining digit is a 2 and it can go in any of the 5 positions so there are 5 items with exactly 4 of the digits being 5. 25555 What if exactly 3 of the digits are 5? That would mean that exactly 2 of the digits are 2. Suppose the leftmost 2 is in the first position. Where could the other 2 go? 22555 Suppose the leftmost 2 is in the second position. Where could the other 2 go? Can you complete the list? Penny  


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