I calculated as follows:
7 usable digits (0,1,2,3,4,5,6)
We need to find numbers greater than 3,00,000. hence,
1) [3] [] [] [] [] [last digit can be any of 0,2,4,6.ie. 4 ways to select last digit]
2) [4] [] [] [] [] [any of 4 even digits]
3) [5] [] [] [] [] [any of 4 even digits]
4) [6] [] [] [] [] [any of 4 even digits]
We have used up 2 out of 7 digit, we are left with 5 digits
Total number of ways to select 1st selection = 1*5*4*3*2*4 = 480 ways
but this is similar to remaining 3 cases...hence each case will have 480 ways
total number of ways = 480*4 = 1920 ways.
Is this correct? if not what am I missing and where?
