How many Three digit numbers can be formed from the digits 2, 3, 5, 6, 7 and 9, which are divisible by 5 and none of the digits is replaced?  Select.
A) 5
B) 10
C) 15
D) 20
E) 30
Since each desired number is divisible by 5, so we must have 5 at the unit place. So, there is 1 way of doing it.   Tens place can be filled by any of the remaining 5 numbers.   So, there are 5 ways of filling the tens place.   The hundreds place can now be filled by any of the remaining 4 digits. So, there are 4 ways of filling it.   Therefore Required number of numbers = 1 x 5 x 4 = 20.   Answer 20.
<result>D</result>
How many Three digit numbers can be formed from the digits 2, 3, 5, 6, 7 and 9, which are divisible by 5 and none of the digits is replaced?