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Bunuel
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If working at continuous rates Harold can wash 12 windows in 6 hours, 04 Apr 2017, 04:47
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E
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80% (01:32) correct 20% (01:50) wrong based on 179 sessions

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If working at continuous rates Harold can wash 12 windows in 6 hours, Melvin can wash 12 windows in h hours, and together they can wash 18 windows in 3 hours, what is the value of h?

A. 12
B. 9
C. 6
D. 4
E. 3
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E
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If working at continuous rates Harold can wash 12 windows in 6 hours, 04 Apr 2017, 05:55
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Bunuel
If working at continuous rates Harold can wash 12 windows in 6 hours, Melvin can wash 12 windows in h hours, and together they can wash 18 windows in 3 hours, what is the value of h?

A. 12
B. 9
C. 6
D. 4
E. 3
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Hi,

Harold can wash 12 windows in 6 hours => Harold cleans 2 windows/hr

In 3 hours, Harold can wash 3*2 = 6 windows.

together they can wash 18 windows in 3 hours => Melvin can wash 18 - 6 = 12 windows in 3 hours.

Answer: E

Thanks.
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If working at continuous rates Harold can wash 12 windows in 6 hours, 04 Apr 2017, 06:12
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Bunuel
If working at continuous rates Harold can wash 12 windows in 6 hours, Melvin can wash 12 windows in h hours, and together they can wash 18 windows in 3 hours, what is the value of h?

A. 12
B. 9
C. 6
D. 4
E. 3
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Using the formula RT = W we can establish ( 12/h + 12/6) * 3 = 18.

Next I tried with answer choices and E) satisfies this equation.

Answer : E
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If working at continuous rates Harold can wash 12 windows in 6 hours, 04 Apr 2017, 13:18
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My approach

12...... 6 hrs
12...... h hrs
18.......3 hrs

12......6 hrs
12......h hrs
12......2 hrs

1/6 + 1/h = 1/2
1/h = 1/2 - 1/6
1/h = 3/6 - 1/6
1/h = 2/6
h = 3

Answer is E
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If working at continuous rates Harold can wash 12 windows in 6 hours, 09 Apr 2017, 09:14
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Harold can wash 12 windows in 6 hours, it means he can wash 6 windows in 3 hours.
That means that Melvin, washed 18-6=12 windows in 3 hours. That clearly means that h=3. Ans E
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If working at continuous rates Harold can wash 12 windows in 6 hours, 18 Apr 2017, 16:11
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Bunuel
If working at continuous rates Harold can wash 12 windows in 6 hours, Melvin can wash 12 windows in h hours, and together they can wash 18 windows in 3 hours, what is the value of h?

A. 12
B. 9
C. 6
D. 4
E. 3
Show more


We are given that Harold can wash 12 windows in 6 hours, Melvin can wash 12 windows in h hours, and that together they can wash 18 windows in 3 hours. Thus, the rate of Harold is 12/6 = 2 windows per hour, the rate of Melvin is 12/h windows per hour, and the combined rate is 18/3 = 6 windows per hour. Let’s create the following equation to determine n:

2 + 12/h = 6

12/h = 4

12 = 4h

h = 3

Answer: E
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If working at continuous rates Harold can wash 12 windows in 6 hours, 18 Aug 2023, 09:29
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