Question

A combination question

Answer 1

How many 4-digit numbers can be made from the numbers 1,3,5,7,9 and 0 if the numbers can be repeated (Remember - a number cannot start with 0)

Answer 2

You have six digits to work with, each of which can be repeated.
So, I'd say your answer is 6*6*6*6
which equals 36*36 which equals
1,296

Answer 3

Nope, its 1080 :/
(remember at 0 cannot be used in the start)

Answer 4

okay then - sorry

Answer 5

@wolf1728, I got it!

Answer 6

_ * _ * _ *_
The first number can't be 0, so you you have 5 numbers to work with for the first spot.
5 * _ * _ * _
The other ones can repeat, so we can fill the other spots with all numbers - 6
5 * 6 * 6 * 6 = 1080.