Question

Ramond is buying boxes of party favors for his sons party .He has to decide how many boxes he should purchase .

A formula for this scenario is :
z=fc/n

z=number of boxes
f=number of favors each child will get
c=number of children at the party
n=number of party favors per box

25 children will attend the party . if each child gets 3 party favors and there are 15 favors in each box, how many boxes should ramond buy ?

(please help)!!!!!!!!!!!!!