the pool with water.
2007-09-27 17:29:57 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
the pool with water
a. 12 min
b. 15 min
c. 21 min
d. 23 min
e. 28 min
2007-09-27 17:33:01 · update #1
Let volume of water in pool = V units ³
Rates of Fill
Jim : V / 30 units ³ / min
Sue : V / 45 units ³ / min
Toni : V / 90 units ³ / min
Working together they fill:-
3V/90 + 2V/90 + V/90 units ³ / min
= 6V/90 units ³ / min
= 2V/30 units ³ / min
Time = V / (2V/30) min = 30V/2V min = 15 min
2007-09-27 22:26:16 · answer #1 · answered by Como 7 · 1⤊ 0⤋
In 15 minutes: Jim will have filled up 1/2 of pool. Sue will have filled up 1/3 of pool. Toni will have filled up 1/6 of pool. The sum of these is 1 pool, so the minimum time for all three to jointly fill a pool is 15 minutes.
2007-09-27 17:44:19 · answer #2 · answered by DannyM 1 · 0⤊ 0⤋
Ok - here's what I think.
In 1hr and 30 minutes, Toni would be able to fill up 1 pool.
Sue would be able to fill up 2 pools in that same time.
Meanwhile, Jim would be able to fill up 3 pools in that time.
So in 90 minutes, the three of them would be able to fill up 6 pools in total.
So if the three together can fill 6 pools in 90 minutes, on average, they can fill 1 pool in 15 minutes.
The answer is 15 minutes.
Hope this helps.
2007-09-27 17:46:45 · answer #3 · answered by pyz01 7 · 0⤊ 0⤋
b.15 minutes
Jim=15min to fill up 3/6
Sue=15min to fill up 2/6
Toni=15min to fill up 1/6
3/6+2/6+1/6=1
So it takes 15mins for them all to fill up the pool together.
2007-09-27 17:38:25 · answer #4 · answered by Anonymous · 0⤊ 0⤋
Add all of them and divide by 3 for the average.
2007-09-27 17:38:14 · answer #5 · answered by housemouse62451 4 · 0⤊ 1⤋