Answer:
total 900 pass codes can be made.
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.