Question

raven can build a brick wall in 8 hours, while her apprentice can do the job in 12 hours. how long does it take for them to build a wall together? how much of the job does raven complete in one hour?

Answer 1

Raven can build 1/8 of the wall in one hour.

Raven's apprentice can build 1/12 of the wall in one hour.

Together, Raven and her apprentice can build 1/x of the wall in one hour.

1/8 + 1/12 = 1/x

3/24 + 2/24 = 1/x

5/24 = 1/x

x = 24/5 = 4.8 hours (4 hours, 48 minutes)

In that time:

Raven: 4.8/8 = 3/5 of the wall

Raven's apprentice: 4.8/12 = 2/5 of the wall