Problem Solving (PS) | How many positive integers less than 9999 are there in which the sum o

0006 - 4!/3! ways
1500 - 4!/2! ways
2400 - 4!/2! ways
3300 - 4!/2!2! ways
2220 - 4!/3! ways
1230 - 4! ways
1113 - 4!/3! ways

Add all: 66 ways. But answer is not matching.

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