A 4digit PIN number must be selected to lock your ipad The d

A 4-digit PIN number must be selected to lock your ipad. The digits 0 to 9 can be used for each number in the PIN and numbers can be repeated (e.g. 2332 is a valid pin).

How many different PIN numbers are possible?

Solution

_ _ _ _ represents 4 digits .

1st number can take any value from 0 to 9. As repetition is allowed . Other 3 numbers can also take any value from 0 to 9.

Hence ,Total cases= 10*10*10*10 = 10000