Question

How many 3-digit number can be formed from the digits 2, 3, 5,6, 7 and 9. Which are divisible by 5 and none of the digits is repeated?

• A. 5
• B. 10
• C. 15
• D. 20

Answer 1

Answer:

D. 20

Since each desired number is divisible by 5, so we must have 5 at the unit place. So, there is I 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. Required number of numbers = (1x5x4)=20