Question
Mathematics Question on Permutations
The number of numbers between 2,000 and 5,000 that can be formed with the digits 0,1,2,3,4 (repetition of digits is not allowed) and are multiple of 3 is :
A
24
B
30
C
36
D
48
Answer
30
Explanation
Solution
Number between 2,000 and 5,000 is 4 digits number.
Using 0,1,2,3,4 (repetition of digits is not allowed) and are multiple of 3 .
For multiple of 3 , the sum of all digits should be divisible by 3
So, number can be formed 0,1,2,3 (sum is 6 which is divisible by 3) or 0,2,3,4 (sum is 9 which is divisible 1 cannot be on highest digit in the number.
Therefore, number of 4 digit numbers =2×3!+3×3!=30