At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
7 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.
I dont understand why it's 7*6 @AkashdeepDeb
how do i even know what 7*6 calculates
If 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?
7*6 calculates the volume of the pool, per se. Basically, it remains constant, because, obviously, the pool's volume won't change.
hmmmmm.... trying to process this in my head
60*x / 120
Ohkay. 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.
can i do proportions with this?
It's just like the basic equation: \(Time * Speed = Distance\) The Distance, always remains constant. In your case, the volume of pool is constant.
ok got it i think
did u want some help with this, you bumped it up?
do u have a different interpretation?
well there was a great trick suggested already
let h be hours 7*6 = 4*h, is a nice simplification, but the logic behind it, u have to think about it a little
why is it 7*6
it doesnt have to it, this relation just exists between the 7 and 4 and the number of hours
Here is another way to approach the problem, okay lets just say there is some work W, that needs to be done
7 pumps take 6 hours to complete this work,, which means each pump worked for 6 hours
7 of these pumps worked for 6 hours in total
okay so lets say it was just 1 pump, its pretty logical to say this 1 pump has to work 7 times more hours right
now when its 4 pumps, that means we have to work 7/4 times more xD
so 7/4 * 6 is our hours,
hmmmm i see
so it's proportions?
here is another way that 7*6 = 4*h relationship comes up
i forgot what i was about to say xD
i 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
does that make sense to you?
okay i think i got it... thanks guys
no problem there are many ways to solve a problem just use the easiest for you!