Question

How many 3 digit pass codes can be made from the digits 0 to 9 if the first number is not allowed to be a 0?

Answer 1

Answer:

total 900 pass codes can be made.

Step-by-step explanation:

Given situation is 3 digit pass codes are required made from the digits 0 to 9.

But the first number is not allowed to be a 0.

So for the third place we have 10 choices ( 0,1,2,3,4,5,6,7,8,9 )

For the second place we have 10 choices ( 0,1,2,3,4,5,6,7,8,9 )

But for the first place we have 9 choices ( 1,2,3,4,5,6,7,8,9 )

( 9 × 10 × 10 ) = 900

Therefore, total 900 pass codes can be made from the digits 0 to 9.