Question

How many 5-digit numbers can be formed from using numbers 0-9?

Answer 1

90 000 possibilities

Explanation:

I will assume that numbers beginning with 0 are not valid

AND assume you can repeat the numbers

9 choices for first digit ( because you can't use ' 0 ' )

10 choices for second

10 choices for third

10 choices for fourth

10 choices for last

9 x 10 x 10 x 10 x 10 = 90 000

Answer 2

100,000

Explanation:

From 0 to 99,999.

99,999 + 1 = 100,000

Also, there are 5 digits, and each digit can be one of ten.

10 × 10 × 10 × 10 × 10 = 100,000