Posted by Anonymous on .
Jim can fill a pool in 30 min, sue can do it in 45 min, Tony can do it in 90min, how long would it take all three to fill the pool together? How would i figure this out?

Math 
Ms. Sue,
See Related Questions below.

Math 
Reiny,
Jim's rate = pool/30
Sue's rate = pool/45
Tony'rate = pool/90
combined rate = pool/30 + pool/45 + pool/90
= (3pool + 2pool + pool)/90 = 6pool/90
= 2pool/30
time to fill pool with combined rate
= pool/(2pool/30)
= 1/(2/30)
= 15 
Math 
Anonymous,
Im still not sure how you are geting the (3pool+2pool+pool) where are those numbers coming from?

Math 
Ms. Sue,
Jim can fill 3 pools in 90 minutes; Sue fills 2 pools in 90 minutes . . .

Math 
Anonymous,
oh wow thank you so much i totally understand now

Math 
Ms. Sue,
You're very welcome.