Question

The number of $4$ digited numbers that can be formed using the digits $1,2,5,6,7$ without repetition and that are divisible by $5$ is

Answer 1

Number is divisible by $5$ if unit place is $5.$ Remaining $3$ places are filled with $4$ digits in ${}^4{P}_3$ ways
$\therefore \text{Number of numbers divisible by}5={}^4{P}_3\times 1=24$