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A pipe P can fill an empty 100-liter tank in 5 hours. Due to dirt accu 11 Jun 2020, 04:12
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A pipe P can fill an empty 100-liter tank in 5 hours. Due to dirt accumulating in the pipe, the rate of supplying water from the pipe reduces by 2 l/hr every 30 minutes. What percentage of the tank will be filled in 2.5 hours?

A. 40
B. 45
C. 50
D. 60
E. 65
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A
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A pipe P can fill an empty 100-liter tank in 5 hours. Due to dirt accu 11 Jun 2020, 04:24
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Rate at which pipe P fills the tank = 20 L/H = 10L/Minute

If there was no dirt, then the capacity of the tank filled would be = 2.5*20 = 50L

Loss because of dirt = 2*5 = 10L

=> Actual capacity filled = 50-10 = 40L
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A pipe P can fill an empty 100-liter tank in 5 hours. Due to dirt accu 11 Jun 2020, 04:34
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Initial rate of filling =20lts/hr
Tank filled every 30 mins =
10+ 9 + 8 +7 +6 =40 lts
Option A is the answer

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A pipe P can fill an empty 100-liter tank in 5 hours. Due to dirt accu 11 Jun 2020, 08:44
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Bunuel
A pipe P can fill an empty 100-liter tank in 5 hours. Due to dirt accumulating in the pipe, the rate of supplying water from the pipe reduces by 2 l/hr every 30 minutes. What percentage of the tank will be filled in 2.5 hours?

A. 40
B. 45
C. 50
D. 60
E. 65
Show more

normal rate of tank being filled ; 100/5 ; 20 lt/hr
after dirt rate per hour reduces by 4 ltr/hr
net effective rate becomes; 16 ltr/hr
so in 2.5 *16 ; 40 lts
which is 40% of original tank capacity i.e 100 ltrs
OPTION A
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A pipe P can fill an empty 100-liter tank in 5 hours. Due to dirt accu 11 Jun 2020, 10:22
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RaghavKhanna
Rate at which pipe P fills the tank = 20 L/H = 10L/Minute

If there was no dirt, then the capacity of the tank filled would be = 2.5*20 = 50L

Loss because of dirt = 2*5 = 10L

=> Actual capacity filled = 50-10 = 40L
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Please explain how did you arrive at loss because of dirt = 2*5? Since the loss decreases after every 30 mins.

Thanks
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A pipe P can fill an empty 100-liter tank in 5 hours. Due to dirt accu 15 Jun 2020, 06:48
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manikmehta95
RaghavKhanna
Rate at which pipe P fills the tank = 20 L/H = 10L/Minute

If there was no dirt, then the capacity of the tank filled would be = 2.5*20 = 50L

Loss because of dirt = 2*5 = 10L

=> Actual capacity filled = 50-10 = 40L

Please explain how did you arrive at loss because of dirt = 2*5? Since the loss decreases after every 30 mins.

Thanks
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Hi manikmehta95

Initially without dirt :
Water filled Litres every Hour \(\hspace{2mm} \) 20 20 20 20 20 ( 5 Hours)
Every half hour Litres\(\hspace{15mm} \) 10 10 10 10 10 ( Total 2.5 hrs)

With Dirt : Water filled per hour Litres \(\hspace{0mm} \) 20 18 16 14 12 ( because 2L/h reduction )
Every half hour Litres filled\(\hspace{18mm} \) 10 \(\hspace{1mm} \) 9 \(\hspace{1mm} \) 8\(\hspace{1mm} \) 7\(\hspace{1mm} \) 6 ( 2.5 hours )

So 10+9+8+7+6 =40 Hence % of water filled \(\frac{40}{100}\)*100 =40 %

Hope it's clear.
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A pipe P can fill an empty 100-liter tank in 5 hours. Due to dirt accu 15 Jun 2020, 10:01
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stne
manikmehta95
RaghavKhanna
Rate at which pipe P fills the tank = 20 L/H = 10L/Minute

If there was no dirt, then the capacity of the tank filled would be = 2.5*20 = 50L

Loss because of dirt = 2*5 = 10L

=> Actual capacity filled = 50-10 = 40L

Please explain how did you arrive at loss because of dirt = 2*5? Since the loss decreases after every 30 mins.

Thanks

Hi manikmehta95

Initially without dirt :
Water filled Litres every Hour \(\hspace{2mm} \) 20 20 20 20 20 ( 5 Hours)
Every half hour Litres\(\hspace{15mm} \) 10 10 10 10 10 ( Total 2.5 hrs)

With Dirt : Water filled per hour Litres \(\hspace{0mm} \) 20 18 16 14 12 ( because 2L/h reduction )
Every half hour Litres filled\(\hspace{18mm} \) 10 \(\hspace{1mm} \) 9 \(\hspace{1mm} \) 8\(\hspace{1mm} \) 7\(\hspace{1mm} \) 6 ( 2.5 hours )

So 10+9+8+7+6 =40 Hence % of water filled \(\frac{40}{100}\)*100 =40 %

Hope it's clear.
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Hi stne

Thanks for your reply. Actually i could get the answer earlier. My only doubt that how did raghavkhanna calculate Loss because of dirt = 2*5 = 10L

Thanks
manik
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A pipe P can fill an empty 100-liter tank in 5 hours. Due to dirt accu 29 Apr 2021, 03:03
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Every 30 minutes there is a loss of 2 Ltrs.

2.5 hrs has 5 cycles of 30 minutes each

Therefore, 5 (30 min cycles) * 2 (loss in every cycle) = 10

Remove the loss (10 Ltrs) from actual water filling capacity i.e., 20 * 2.5 = 50, which is 50-10 = 40
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A pipe P can fill an empty 100-liter tank in 5 hours. Due to dirt accu 22 Jan 2024, 21:01
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