The difference between the greatest and smallest 6-digit numbers formed by using the digits 5, 1, 0, 3, 9 and 6 is:

Digits: 5, 1, 0, 3, 9, 6

Greatest number → arrange digits in descending order.

Smallest number → arrange digits in ascending order (but the first digit can’t be 0).

Difference = Greatest − Smallest

Solution:
Greatest number = 9 6 5 3 1 0 = 965310
Smallest number = 1 0 3 5 6 9 = 103569
Difference = 965310 − 103569

Now subtract carefully:
965310 − 103569 = 861741