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divyajoshi12
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4 identical taps can fill a 100 liter tank in 6 hours, then 06 Sep 2018, 10:19
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15% (low)

Question Stats:

80% (01:35) correct 20% (01:57) wrong based on 293 sessions

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4 identical taps can fill a 100 liter tank in 6 hours, then how many hours will be required to fill a 150 liter tank by 8 such taps?

A. 3
B. 4
C. 5
D. 4.5
E. 3.5
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D
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generis
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4 identical taps can fill a 100 liter tank in 6 hours, then 06 Sep 2018, 19:25
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divyajoshi12
4 identical taps can fill a 100 liter tank in 6 hours, then how many hours will be required to fill a 150 liter tank by 8 such taps?

A) 3
B)4
C)5
D)4.5
E)3.5
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Change the standard RT=W formula.
Add "# of machines" (taps, workers, whatever) to LHS.
Manipulate it just as you would the standard formula.
(# of machines) * Rate * Time = Work

Scenario #1 Find individual tap rate:
4 identical taps can fill a 100L tank in 6 hrs

(# of machines) * R * T = W
\(4*R*6=100\)
\(R*24=100\)
\(R=\frac{100}{24}=\frac{25}{6}\)

At that rate for an individual tap, how many hours will it take for 8 such taps to fill a 150L tank?

Scenario #2: Find time needed in the new scenario.
Use the rate just calculated.

(# of machines) * R * T = W
\(8*\frac{25}{6}*T=150\)
\(T*\frac{200}{6}=150\)
\(T*\frac{100}{3}=150\)
\(T=(150*\frac{3}{100})=(3*\frac{3}{2})=\frac{9}{2}=4.5\) hours

Answer D
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Bismarck
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4 identical taps can fill a 100 liter tank in 6 hours, then 06 Sep 2018, 10:30
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divyajoshi12
4 identical taps can fill a 100 liter tank in 6 hours, then how many hours will be required to fill a 150 liter tank by 8 such taps?

A) 3
B)4
C)5
D)4.5
E)3.5

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OA: D

Water filled by 1 taps per hour \(= \frac{100}{6*4}\) Litre/hr

Water filled by 8 taps per hour \(= \frac{8*100}{6*4}\)Litre/hr

Time taken by 8 taps to fill 150 litre\(= \frac{150}{\frac{8*100}{6*4}}\)hr \(=\frac{150*6*4}{8*100}\)hr \(= 4.5\)hr
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Kritika2008poddar
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4 identical taps can fill a 100 liter tank in 6 hours, then 06 Sep 2018, 10:39
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We can also do it in more simple way i.e. let's calculate the time it takes to fill 150 ltrs by 4 taps

=6/100*150 = 9 hours
Now since the taps are identical, we can simply half the time taken by 8 taps

=4.5 hrs

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4 identical taps can fill a 100 liter tank in 6 hours, then 06 Sep 2018, 19:44
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6*(4/8)*(150/100)=4.5

First term is original time.
Second term 4/8 as time will decrease on increasing taps.
Third Term 150/100 as time will increase on increasing work.
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4 identical taps can fill a 100 liter tank in 6 hours, then 28 Jan 2020, 02:15
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4 taps 100 litres 6 hours -> 1 tap per hour 100/6*4 = 100/24

8 taps 150 litres X houts -> 8 taps per hour 8*100/24 = 800/24

8 taps filling 150 litres= 150 / 800 /24 = 150 * 24 / 800 = 4.5
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4 identical taps can fill a 100 liter tank in 6 hours, then 04 Dec 2024, 02:02
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