4,2,2,5,5,5,5
7!/(2!4!) =105
4,4,1,5,5,5,5
Same, 105
8,2,1,5,5,5,5
7!/4!=210
So total is 420
How many 7 digit positive integers are there such that the product of the individual digits of each number is equal to 10000?
1 answer