An experience bricklayer can construct a small wall in 3 hours. An apprentice can complete the job in 5 hours. Find how long it takes if they work together. Show work.

Step-by-step explanation:

If the bricklayer can construct the wall in its entirety in 3 hours, then he can get 1/3 of the job done in an hour.

If the apprentice can get the whole job done in 5 hours, then he can get 1/5 of the job done in an hour. If they both work together on said job, the equation is

and now we solve for x. Multiply everything by the LCM to get rid of the fractions. That would be 15x:

and doing that gives us

5x + 3x = 15 and

8x = 15 so

x = 1.875 hours which is 1 7/8 hours which is also 1 hour and 52 1/2 minutes.