A plumber can complete a job in 2 hours. If an apprentice helps, it takes only 1 1/3 hours. How many hours would it take the apprentice working alone?

Question

It is a proportion problem and I am just having trouble finding the answer.

Answer 1

(1 1/3) / 2 + (1 1/2) / a = 1

(4/3)a + (4/3)2 = 2a              multiply both sides by 2a

(4/3)2 = (2/3)a                      subtract (4/3)a from both sides

8/3 = 2a/3                            simplify

8 = 2a

4 = a