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What is the highest power of 7 in 5000! (five thousand factorial)?
Ans: 832
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5000/7 = 714
714/7 = 102
102/7 = 14
14 / 7 = 2
2 / 7 = 0

714+102+14+2+0 = 832

Don't ask me how. I just know that to identify power of a number in a factorial, u need to sum the successive quotients.