Answer:
He can make a total of x*y*z selections, where x is the amount of suits he bought, y the amount of shirts he bought and z the amount of ties he bought.
Step-by-step explanation:
You probably forgot to mention how many of each kind did he buy.
Let x mean the amount of suits he bought, y the amount of shirts and z the amount of ties. The total amount of combinations that man can make can be computed by multiplying x, y and z: for each of the x suits, he can select y shirts, thus he has x*y possibilities to select one shirt and one suit. For each pair of suit and shirt (there are xy in total), he has z possibilities to select a tie, giving us a total of xy*z = xyz ways to select one suit, one shirt and one tie.
