Question

The difference between the greatest
and the smallest 6-digit numbers made by
using all of 0, 4, 6 and 8 (digits can be repeat)​

Answer 1

Answer:

Case1: Each digit must be used.

In this case the greatest six digit number is 888640 if all the digits have to be used at least once.

The smallest six digit number is 400068.

So, the difference is 888640–400068=488572.

If zero(s) can be used as leading digits, then the smallest number will be 000468 and the difference will be 888172.

Case2:All digits need not be used.

In the extreme case I will take (only digit 8 is used) the largest number is 888888 and smallest is 000000 (Please note it does not have a +ve or -ve value).

So the difference will be 888888–0=888888.

If zero is not allowed we can take 400000 as the smallest number.

So the difference will be 888888–400000=488888.