How many six digit numbers greater than 700 000 can be made from the digits 2, 2, 4, 4, 4, 7?

A. 10
B. 60
C. 64
D. 120

1 answer

If it has to be greater than 700000, the first digit must be 7. That leaves us with 5 digits 2,2,2,4,4 to make the remainder of the number.

Here we have 5 digits of which 2 and 3 are identical, so the number of ways to choose the 5 digits is
C(5,3,2) = 5!/(3!2!)
I'll let you do the rest.