Question:
Number of all four digit numbers having different digits formed of the digits 1, 2, 3, 4 and 5 and divisible by 4 is
Number of all four digit numbers having different digits formed of the digits 1, 2, 3, 4 and 5 and divisible by 4 is
Options:
- 125
- 30
- 24
- 100
- 125
- 30
- 24
- 100
Correct Answer: c)
Explanation:
‘
In order to make a number di√isible by 4, its last two digits must be di√isible by 4, whichin
‘ this case can be 12, 24, 32 or 52
‘ Since repetition of digits is not allowed, the remaining first two digits can be arranged in 3 x ‘
2 ways in each case.
‘ .”. Total number of numbers that can be formed =4 x (3 x 2)=24
) 25.
©a=8
‘
‘
In order to make a number di√isible by 4, its last two digits must be di√isible by 4, whichin
‘ this case can be 12, 24, 32 or 52
‘ Since repetition of digits is not allowed, the remaining first two digits can be arranged in 3 x ‘
2 ways in each case.
‘ .”. Total number of numbers that can be formed =4 x (3 x 2)=24
) 25.
©a=8
‘