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anonymous
 one year ago
Working together, 7 identical pumps can empty a pool in 6 hours. How many hours will it take 4 pumps to empty the same pool?
anonymous
 one year ago
Working together, 7 identical pumps can empty a pool in 6 hours. How many hours will it take 4 pumps to empty the same pool?

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AkashdeepDeb
 one year ago
Best ResponseYou've already chosen the best response.27 identical pumps => 6 hours 4 identical pumps => ? hours Statement: More pumps, less time. Inversely proportional. Solution: No. of pumps in 1st case * time taken in 1st case = no. of pumps in second case * time taken in 2nd case. Think of it like this: 42 identical pumps would be needed to do it in 1 hour.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I dont understand why it's 7*6 @AkashdeepDeb

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0how do i even know what 7*6 calculates

AkashdeepDeb
 one year ago
Best ResponseYou've already chosen the best response.2If I travel at 60 km/hr in a car, I can cover a distance x in 1 hour. If I travel at 120 km/hr can you guess how much time it'll take to cover the same distance?

AkashdeepDeb
 one year ago
Best ResponseYou've already chosen the best response.27*6 calculates the volume of the pool, per se. Basically, it remains constant, because, obviously, the pool's volume won't change.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0hmmmmm.... trying to process this in my head

AkashdeepDeb
 one year ago
Best ResponseYou've already chosen the best response.2Ohkay. Let me use a similar example. I want to right a book with a fixed number of words. I can right 30 words per minute for 10 minutes. If I can increase my speed to 60 words per minute, how much time will it take me to write the book? See, what's happening here. I STILL have to write the same number of words! If I can finish writing a book by writing at 30 words per minute for 10 minutes, I am writing 30 * 10 words = 300 words. Now, if I write a 60 words per minute, I still have to write 300 words. That would take me 300/60 = 5 minutes to write.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0can i do proportions with this?

AkashdeepDeb
 one year ago
Best ResponseYou've already chosen the best response.2It's just like the basic equation: \(Time * Speed = Distance\) The Distance, always remains constant. In your case, the volume of pool is constant.

dan815
 one year ago
Best ResponseYou've already chosen the best response.0did u want some help with this, you bumped it up?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0do u have a different interpretation?

dan815
 one year ago
Best ResponseYou've already chosen the best response.0well there was a great trick suggested already

dan815
 one year ago
Best ResponseYou've already chosen the best response.0let h be hours 7*6 = 4*h, is a nice simplification, but the logic behind it, u have to think about it a little

dan815
 one year ago
Best ResponseYou've already chosen the best response.0it doesnt have to it, this relation just exists between the 7 and 4 and the number of hours

dan815
 one year ago
Best ResponseYou've already chosen the best response.0Here is another way to approach the problem, okay lets just say there is some work W, that needs to be done

dan815
 one year ago
Best ResponseYou've already chosen the best response.07 pumps take 6 hours to complete this work,, which means each pump worked for 6 hours

dan815
 one year ago
Best ResponseYou've already chosen the best response.07 of these pumps worked for 6 hours in total

dan815
 one year ago
Best ResponseYou've already chosen the best response.0okay so lets say it was just 1 pump, its pretty logical to say this 1 pump has to work 7 times more hours right

dan815
 one year ago
Best ResponseYou've already chosen the best response.0now when its 4 pumps, that means we have to work 7/4 times more xD

dan815
 one year ago
Best ResponseYou've already chosen the best response.0so 7/4 * 6 is our hours,

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so it's proportions?

dan815
 one year ago
Best ResponseYou've already chosen the best response.0here is another way that 7*6 = 4*h relationship comes up

dan815
 one year ago
Best ResponseYou've already chosen the best response.0i forgot what i was about to say xD

Baseballguy101
 one year ago
Best ResponseYou've already chosen the best response.0i always solve problems like this another way. if you have 7 pumps that empty a pool in 6 hours you can divide the amount of pumps by the time. so 7/6 then times it by the amount of pumps you're using now. so I would use the equation (7/6)*4

Baseballguy101
 one year ago
Best ResponseYou've already chosen the best response.0does that make sense to you?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay i think i got it... thanks guys

Baseballguy101
 one year ago
Best ResponseYou've already chosen the best response.0no problem there are many ways to solve a problem just use the easiest for you!
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