SOLUTION: It takes j 6 hours to lay 100 square feet of tile. It takes k 5 hours to lay 100 square feet of tile. How long will it take them to lay 100 square feet of tile together?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: It takes j 6 hours to lay 100 square feet of tile. It takes k 5 hours to lay 100 square feet of tile. How long will it take them to lay 100 square feet of tile together?      Log On


   

Question 1009926: It takes j 6 hours to lay 100 square feet of tile. It takes k 5 hours to lay 100 square feet of tile. How long will it take them to lay 100 square feet of tile together?
Found 2 solutions by ikleyn, Boreal:
Answer by ikleyn(52767) About Me  (Show Source):
You can put this solution on YOUR website!
.
1%2F6 + 1%2F5 = 5%2F30 + 6%2F30 = 11%2F30.

Hence, it will take 30%2F11 of an hour for J and K to lay 100 ft%5E2 of tile working together.

For details, see the lesson Using fractions to solve word problems on joint work in this site.


Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
in x hours, j lays x/6 of the tile.
in x hours, k lays x/5 of the tile.
Together, they lay (x/6)+(x/5)=1 room.
multiply everything by 30.
5x+6x=30
11x=30
x=30/11, or 2.73 hours