Question

Martin uses 5/8 of a gallon of paint to cover 4/5 of a wall. What is the unit rate at which Martin paints in walls per gallon?

Answer 1

Remember, (a/b)/(c/d)=(a/b)(d/c)=(ad)/(bc)

so

walls per gallon
4/5 wall per 5/8 gallon
(4/5)/(5/8)
(4/5)(8/5)
32/25
1.28
the unit rate is 1.28 walls per gallon