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Bunuel
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There are three foam generators in the factory, the first two can gene 27 Jun 2016, 04:08
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45% (medium)

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76% (02:46) correct 24% (02:55) wrong based on 273 sessions

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There are three foam generators in the factory, each of the first two can generate 14 liters of foam in one hour and the third can generate 18 liters in an hour. The three generators start working together at the same time and after one hour and a half one of the first generators stops working and two hours after that the third generator stops working and only one generator is left. If 5 hours after they all started to work the last generator stops working, how many liters of foam were generated?

A. 120.
B. 132.
C. 146.
D. 154.
E. 166.
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D
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There are three foam generators in the factory, the first two can gene 27 Jun 2016, 06:01
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Assuming each of the first two can generate 14 litres !!

foam generated for first one and half hours = 42+27= 69 litres
now one of the first generator has stopped working
foam generated for the next two hours = 28+36=64 litres
now the third generator has stopped working
foam generated for the remaining one and half hour = 21
total foam generated = 154 litres
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There are three foam generators in the factory, the first two can gene 27 Jun 2016, 07:04
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Bunuel
There are three foam generators in the factory, each of the first two can generate 14 liters of foam in one hour and the third can generate 18 liters in an hour. The three generators start working together at the same time and after one hour and a half one of the first generators stops working and two hours after that the third generator stops working and only one generator is left. If 5 hours after they all started to work the last generator stops working, how many liters of foam were generated?

A. 120.
B. 132.
C. 146.
D. 154.
E. 166.
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A method other then mentioned above and may be slightly easy in calculations is TO work out works of each foam separately..
1) First - 14 ltr/hr for \(1 \frac{1}{2} hr = 14 *\frac{3}{2} = 21\) ltr..
2) second - 14 ltr/hr for \(5 hr = 14 *5 = 70\) ltr..
3) third - 18 ltr for \(3 \frac{1}{2} hour = 18*\frac{7}{2} = 63\)..
Total = \(21+70+63 = 154..\)

Also a method dependent on choices...
the WORK of first two is a multiple of 7 since their capacities are 14 lph and WORK of third will also be multiple of 7 as the hours are 3.5, a multiple of 7..
ONLY 154 is multiple of 7...
D
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There are three foam generators in the factory, the first two can gene 27 Jun 2016, 11:29
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Bunuel
There are three foam generators in the factory, each of the first two can generate 14 liters of foam in one hour and the third can generate 18 liters in an hour. The three generators start working together at the same time and after one hour and a half one of the first generators stops working and two hours after that the third generator stops working and only one generator is left. If 5 hours after they all started to work the last generator stops working, how many liters of foam were generated?

A. 120.
B. 132.
C. 146.
D. 154.
E. 166.
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Let the foam generators capacity be -

A = 14 lit/hr
B = 14 lit/hr
C = 18 lit/hr

Total foam generation in 1 hour will be 46 lit ( 14 + 14 + 18 ) ; since in 1 and 1/2 hr they will generate 46 + 23 => 69 litres...

Now one of the first generators stops working ( Say A stops working ) , so we have -

B = 14 lit/hr
C = 18 lit/hr

Total foam generation in 2 hour will be 64 litres {2 (14+18)}

The third generator stops working and now only B works for the remaining time 1 and 1/2 ( 5 - 1 and 1/2 - 2 )...

Foam generated by B will be 3/2 * 14 => 21 litres


So, total foam generated will be 154 Litres ( 69 + 64 + 21 ) ; hence answer will be (D)
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There are three foam generators in the factory, the first two can gene 27 Jun 2016, 20:36
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Hour 1: All three work - Foam Generated- 14 + 14 + 18
Hour 1.5 : All three work for 30 more minutes after hour 1- Foam Generated(50 % of hour 1) - 7+7+9

Total Foam Till now : 46 + 23 = 69 Ltrs


Next 2 hours only 2nd and third work - Foam Generated - 21 + 27 + 16 = 64

Next 1.5 hours only Gen 2 works - Foam Generated - 7 * 3 = 21

Total Foam Generated :69 + 64 + 21


Last Digit ends in 4 so Ans is D
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There are three foam generators in the factory, the first two can gene 10 May 2018, 23:43
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Bunuel
There are three foam generators in the factory, each of the first two can generate 14 liters of foam in one hour and the third can generate 18 liters in an hour. The three generators start working together at the same time and after one hour and a half one of the first generators stops working and two hours after that the third generator stops working and only one generator is left. If 5 hours after they all started to work the last generator stops working, how many liters of foam were generated?

A. 120.
B. 132.
C. 146.
D. 154.
E. 166.
Show more

Rate of Ist pump = 14 lt/hr ------ Worked for 1.5 hrs ---- Foam generated = 1.5 * 14 = 21 litres

Rate of second pump = 14 lt/hr ------- Worked for 5 hrs ----- Foam generated = 14 * 5 = 70 litres

Rate of third pump = 18 lt/hr ------ Worked for 3.5 hrs ------ Foam generated = 18*3.5 = 63 litres

Total foam generated = 21+70+63 = 154 litres

(D)
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There are three foam generators in the factory, the first two can gene 14 May 2018, 16:52
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Bunuel
There are three foam generators in the factory, each of the first two can generate 14 liters of foam in one hour and the third can generate 18 liters in an hour. The three generators start working together at the same time and after one hour and a half one of the first generators stops working and two hours after that the third generator stops working and only one generator is left. If 5 hours after they all started to work the last generator stops working, how many liters of foam were generated?

A. 120.
B. 132.
C. 146.
D. 154.
E. 166.
Show more

Let’s call the 3 generators A, B and C. So the rate of A = rate of B = 14 and the rate of C = 18. Let’s also assume that A is the generator that stops working after 1½ hours. So A works for 1½ = 1.5 hours, C works 1.5 + 2 = 3.5 hours, and B works for 5 hours. Therefore the total number of liters of foam generated is:

14(1.5) + 14(5) + 18(3.5) = 21 + 70 + 63 = 154

Answer: D
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There are three foam generators in the factory, the first two can gene 10 Nov 2025, 07:26
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