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how many four digit numbers can be formed such that the digits are in the decreasing order

Dharani Lakshmanan , 10 Years ago
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anser 1 Answers
Shobhit Varshney

Last Activity: 10 Years ago

Dear student,

Number of such numbers without having zero in the number = (9*8*7*6) / 4! = 126
Number of such numbers with having zero in the number = (9*8*7) / 3! = 84

Therefore, number of such numbers = (126+84) = 210
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