Question

how many four digit number can be formed using the digit 0,4,1,8​

Answer 1

Answer:

3

Step-by-step explanation:

4180

8140

1480

4081

1048

Answer 2

Answer:

If repetition is allowed = 192

If repetition is not allowed = 18

Step-by-step explanation:

Repetition allowed:

Here,are four vacant places to be filled,

In the first one we can only add 3 numbers as 0 can't be added.

In the second one,we can add 4 digits

[Beacuse repetition is allowed]

Similarly,in the 3rd and 4th place we can add 4 digits

and thus no.of possible four digits numbers = 3×4×4×4

=192

Repetition not allowed:

Here,in the first place we can add 3 digits as 0 can't be added.

Then,in 2nd place = 3 digits

in 3rd place = 2 digits

in 4th place = 1 digits

Thus,no. of possible four digit numbers = 18