Aptitude Discussion

Q. |
A five-digit number is formed by using digits 1, 2, 3, 4 and 5 without repetition. What is the probability that the number is divisible by 4? |

✔ A. |
1/5 |

✖ B. |
5/6 |

✖ C. |
4/5 |

✖ D. |
None of these |

**Solution:**

Option(**A**) is correct

A number divisible by 4 formed using the digits 1, 2, 3, 4 and 5 has to have the last two digits 12 or 24 or 32 or 52.

In each of these cases, the five digits number can be formed using the remaining 3 digits in $3! = 6$ ways.

A number divisible by 4 can be formed in $6×4 = 24$ ways.

Total number that can be formed using the digits 1, 2, 3, 4 and 5 without repetition

$= 5! = 120$

Required probability,

$= 24/120$

$= \textbf{1/5}$

**S Malik**

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any one please explain it with another method...