A person has 5 chocolates of different sizes and they are to be distributes among 5 children of different ages. If the biggest chocolate is to be given to the youngest child, then remaining 4 chocolates can be distributed among the remaining 4 children in 4P4 ways.
∴ Total permutations = 1P1 x 4P4
= 1 × 4!
= 1 × 24
= 24