SOLUTION: Jim can fill a pool carrying buckets of water in 30 minutes. Sue can do the same job in 45 minutes. Tony can do the same job in 1 ½ hours. How quickly can all three fill the pool t

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Jim can fill a pool carrying buckets of water in 30 minutes. Sue can do the same job in 45 minutes. Tony can do the same job in 1 ½ hours. How quickly can all three fill the pool t      Log On


   

Question 263107: Jim can fill a pool carrying buckets of water in 30 minutes. Sue can do the same job in 45 minutes. Tony can do the same job in 1 ½ hours. How quickly can all three fill the pool together?
A. 12 minutes
B. 15 minutes
C. 21 minutes
D. 23 minutes
E. 28 minutes

Found 2 solutions by richwmiller, josmiceli:
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
x/30+x/45+x/90=1
3x+2x+x=90
6x=90
x=90/6=30/2=15
b) 15 minutes

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Add their rates of filling the pool to get
their rate working together
Jim's rate = 1%2F30 or one pool in 30 min
Sue's rate = 1%2F45 or one pool in 45 min
Tony's rate = 1%2F90 or one pool in 90 min
Let x = time it takes for all 3 working together
1%2F30+%2B+1%2F45+%2B+1%2F90+=+1%2Fx
Multiply both sides by 90x
3x+%2B+2x+%2B+x+=+90
6x+=+90
x+=+15
Working together, it takes them 15 min to fill the pool
The answer is B