Solving a word problem involving rates and time conversion

Question

A copy machine makes 24 copies per minute. How long does it take to make 90 copies?

Answer 1

24 : 1 :: 90 : x

24x = 90

Can you solve for x and answer?

Answer 2

num of copies. : time

24. : 1 minute

90. : X minutes

24x =90

x =90/24

x= 3.75mintes