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Bunuel
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A water pump began filling an empty swimming pool with water and ran a 26 Sep 2018, 05:13
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C
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85% (01:46) correct 15% (02:57) wrong based on 282 sessions

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A water pump began filling an empty swimming pool with water and ran at a constant rate til the swimming pool was full. At sometime, the pool was 1/2 full, and 7/3 hours later, it was 5/6 full. How many hours would it take the pump to fill the empty pool completely?

(A) 4
(B) 16/3
(C) 7
(D) 36/5
(E) 25/3
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C
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A water pump began filling an empty swimming pool with water and ran a 28 Sep 2018, 14:18
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We know it was 1/2 then 7/3 hours later it became 5/6 full.

So the difference would be 5/6 - 1/2 = 5/6 - 3/6 = 2/6 = 1/3 in 7/3 hours.

Given that it will fill 1/3 in 7/3 hours.

We want it to fill completely so that would be 7/3 * 3 = 7

Answer choice C

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A water pump began filling an empty swimming pool with water and ran a 15 Dec 2018, 11:40
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My approach (probably not the most efficient).

from 1/2 full to 5/6 full it was 1/3 of total time to fill in the pool.

So 1/2 = 3/6


5/6 - 3/6 = 1/3,

1/3 of the pool was filled in by water in 7/3 hours.

So take 7/3 * 3 and get 21/3 = 7 hours total time to fill in the pool.
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A water pump began filling an empty swimming pool with water and ran a 14 Feb 2020, 05:36
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There is a confusion, if the tank was already 1/2 full then adding 5/6 will make it more than full, no?
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A water pump began filling an empty swimming pool with water and ran a 28 Feb 2020, 08:16
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Bunuel
A water pump began filling an empty swimming pool with water and ran at a constant rate til the swimming pool was full. At sometime, the pool was 1/2 full, and 7/3 hours later, it was 5/6 full. How many hours would it take the pump to fill the empty pool completely?

(A) 4
(B) 16/3
(C) 7
(D) 36/5
(E) 25/3
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Solution:

Since it took 7/3 hours to fill 5/6 - 3/6 = 2/6 = 1/3 of the pool.

The rate is:

(1/3) / (7/3) = 1/7.

So, it takes 1/(1/7) = 7 hours to fill the pool.

Alternate Solution:

It took 2 ⅓ - ½ = 7/3 hours to fill 5/6 - 3/6 = 2/6 = 1/3 of the pool. We can set up a proportion, letting x = the number of hours to completely fill the pool:

(7/3) / (⅓) = x / 1

Cross-multiplying, we obtain:

x/3 = 7/3

x = 7. Thus, it takes 7 hours to fill the pool.


Answer: C
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A water pump began filling an empty swimming pool with water and ran a 28 Apr 2020, 08:39
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Bunuel
A water pump began filling an empty swimming pool with water and ran at a constant rate til the swimming pool was full. At sometime, the pool was 1/2 full, and 7/3 hours later, it was 5/6 full. How many hours would it take the pump to fill the empty pool completely?

(A) 4
(B) 16/3
(C) 7
(D) 36/5
(E) 25/3
Show more

Given:
1. A water pump began filling an empty swimming pool with water and ran at a constant rate til the swimming pool was full.
2. At sometime, the pool was 1/2 full, and 7/3 hours later, it was 5/6 full.

Asked: How many hours would it take the pump to fill the empty pool completely?

In 7/3 hours, pump has filled = 5/6 - 1/2 = 2/6 = 1/3 of swimming pool
In 1 hours, pump will fill = 3/7 * 1/3 = 1/7 of swimming pool

Number of hours, pump will take to fill the empty pool completely = 7 hours

IMO C
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A water pump began filling an empty swimming pool with water and ran a 28 Nov 2023, 04:22
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