A copy machine makes 28 copies per minute. how many copies does it make in 3 minutes and 45 seconds

A copy machine makes 28 copies per minute. how many copies does it make in 3 minutes and 45 seconds?

45 seconds = 45/60 = 3/4 of a minute.
3/4 = 0.75
So we have 3.75 minutes.

Set up a proportion of copies to minutes where c is the number of copies made in 3 minutes and 45 seconds:
28/1 = c/3.75

Typing this proportion into our calculator, we get:
c = 105