Two machines A and B drain water from a tank. A worked alone for 4 hours to
Drain half of the water in the tank. Then, B joined and the remaining water could be drained in 3 hours. In how many hours could B drain the water alone?
I picked up this question from net. Don't have the options. I worked out the answer 24. Wts your opinion?
5) how hard do these machines work?
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1/4+1/x=1/3ern5231 wrote:Two machines A and B drain water from a tank. A worked alone for 4 hours to
Drain half of the water in the tank. Then, B joined and the remaining water could be drained in 3 hours. In how many hours could B drain the water alone?
I picked up this question from net. Don't have the options. I worked out the answer 24. Wts your opinion?
x=12 B can drain half water in 12 hrs therefore alone it can drain in 24 hrs.
- harshavardhanc
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A can drain half of the quantity in 4 hrs i.e 25% in one hour.ern5231 wrote:Two machines A and B drain water from a tank. A worked alone for 4 hours to
Drain half of the water in the tank. Then, B joined and the remaining water could be drained in 3 hours. In how many hours could B drain the water alone?
I picked up this question from net. Don't have the options. I worked out the answer 24. Wts your opinion?
together with B, he's able to drain half the water in 3 hrs, i.e efficiency is increased to 33.33% or by 8.33%. which is 1/12.
hence, B can drain half the tank in 12 hours or full capacity of the tank in 24 hours.
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Harsha
Harsha
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A simple formula that can be handy for any similar type of problem is:ern5231 wrote:Two machines A and B drain water from a tank. A worked alone for 4 hours to
Drain half of the water in the tank. Then, B joined and the remaining water could be drained in 3 hours. In how many hours could B drain the water alone?
I picked up this question from net. Don't have the options. I worked out the answer 24. Wts your opinion?
(A+B) togethar = AB/(A+B) .
6 = 8B/(8+B)
B = 24.
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