Step-by-step explanation:
Remember, math is a language
when you see per think fractions
15.2 miles per hour = 15.2 miles / 1 hour
since this is a fraction, Units can cancel just like numbers
To cancel miles and be left with hours rearrange the fraction
1 hour / 15.2 miles
then multiply by 72 miles

the miles cancel and youre left with hours!
so youd write and solve 72 / 15.2