Ralph takes 2,250 seconds, alone, while Bob takes 1,800 seconds, alone

Time both take, working together:  

Answer by ikleyn(52835)   (Show Source): You can put this solution on YOUR website!
 .

Ralph can lay down a floor tile in 5 seconds. Bob can lay down a floor tile in 4 seconds. 

If both boys work together, how many seconds would it take them to install 450 floor tiles?

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~





Every 20 seconds Ralph lays 4 tiles and Bob lays 5 tiles.
So, every 20 seconds both boys lay 4 + 5 = 9 tiles working together.

 = 50.

Hence, the boys need 50*20 = 1000 seconds to lay all 450 tiles working together.

Answer.  1000 seconds.


 

RELATED QUESTIONS

Jerry can lay a tile floor in 3 hours less time than Jake. If they can work together, the  (answered by Theo,MathTherapy)

Dan can tile a floor in 3 hours. His assistant could tile the same floor in 8 hours. If... (answered by TimothyLamb,Edwin McCravy)

jerry and kuba are laying a hardwood floor. working alone jerry can finish the job in 20... (answered by richwmiller)

Fred is putting down tile down for a new gymnasium. He can lay 25 square feet of tile an... (answered by solver91311)

Jerry and Sam are laying a hardwood floor. Working alone, Jerry can do the job in 20... (answered by josmiceli)

if 3 chickens can lay a dozen eggs in 2 days, how many eggs can 5 chicken lay in 9days?  (answered by ankor@dixie-net.com)

Alan took 4 hours to tile the floor of a room. Gary took 6 hours to tile the floor of the  (answered by josmiceli)

The kitchen floor of your home is 12 feet 6 inches in width and 10 feet 4 inches in... (answered by solver91311)

tutor quick help plz and solution. Ed required 12 hours to lay linoleum tile on his... (answered by mananth)