Question -
Answer -
Number of arrangementsof ‘n’ things taken all at a time = P (n, n)
So by using theformula,
By using the formula,
P (n, r) = n!/(n – r)!
The total number ofways in which five children can stand in a queue = the number of arrangementsof 5 things taken all at a time = P (5, 5)
So,
P (5, 5) = 5!/(5 – 5)!
= 5!/0!
= 5! [Since, 0! = 1]
= 5 × 4 × 3 × 2 × 1
= 120
Hence, Number of waysin which five children can stand in a queue are 120.