How many quarter hours are in 5 hours?

There is a few ways to get the result.
Lets try this.
First calculate how many minutes are in the 5 hours.
60min*5=300min - in 5 hours
Now, knowing that quarter is 15min we can divide 300 by 15 to get the result, so
300:15=20 - its the result.

I would do this with a proportion. we know 4 quarter hours are in 1 hour, so how many are in 5?
4/1 = x/5
cross multiply
1*x=4*5
x=20
there are 20 quarter hours in 5 hours.