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Bunuel
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If a certain factory makes a total of 30,720 wrenches, how many minute 14 Nov 2014, 09:46
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Tough and Tricky questions: Word Problems.



If a certain factory makes a total of 30,720 wrenches, how many minutes does the factory take to make the wrenches?

(1) The factory creates the wrenches without interruption at a rate of 32 wrenches per second.

(2) It takes 4 times as long for the factory to create the wrenches as it does to load them into trucks, and it takes the factory a total of 20 minutes to do both.

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D
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If a certain factory makes a total of 30,720 wrenches, how many minute 14 Nov 2014, 10:17
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Hey Bunuel just wanted to say thanks for always posting new questions each day, it's really helping with my studying! :)

statement A: sufficient
Divide 30,720 by 32 to find out how many seconds it takes to create all of the wrenches. No need to calculate.

statement B: sufficient
Knowing the ratio of time it takes to create to time it takes to load and the total time to do both, we can see that it takes 16 minutes to create the wrenches and 4 minutes to load them (ratio of 4:1)

Answer D!
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If a certain factory makes a total of 30,720 wrenches, how many minute 14 Nov 2014, 13:17
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(1) gives the productivity rate, and since we already know the work, we can calculate the duration. SUFFICIENT

(2) indirectly gives the duration. SUFFICIENT

Answer (D)
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If a certain factory makes a total of 30,720 wrenches, how many minute 14 Nov 2014, 19:01
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Statement 1:
Rate is given as 32 wrenches per second. We can easily calculate minutes required to make the 30,720 wrenches.

Sufficient . Option B,C,E are out

Statement 2:
Let's assume it takes L minutes to load wrenches into trucks and C minutes for the factory to create the wrenches.
From the given statement - C = 4*L, and C + L = 20
We can get minutes required to make the wrenches.

Sufficient

Each statement is sufficient, hence D.
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If a certain factory makes a total of 30,720 wrenches, how many minute 14 Nov 2014, 19:25
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From Statement 1, we can say that :
Time taken to create wrenches= 30,720/ 32*60 = 16 mins. Sufficient

From Statement 2, we can that :
4x+ x =20 [where x is the rate of loading the wrenches to load them to the truck]
Time taken to create wrenches= 4x = 20/5*4 = 16 mins. Sufficient

D) should be the answer
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If a certain factory makes a total of 30,720 wrenches, how many minute 17 Nov 2014, 12:19
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Bunuel

Tough and Tricky questions: Word Problems.



If a certain factory makes a total of 30,720 wrenches, how many minutes does the factory take to make the wrenches?

(1) The factory creates the wrenches without interruption at a rate of 32 wrenches per second.

(2) It takes 4 times as long for the factory to create the wrenches as it does to load them into trucks, and it takes the factory a total of 20 minutes to do both.

Kudos for a correct solution.
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Official Solution:

If a certain factory makes a total of 30,720 wrenches, how many minutes does the factory take to make the wrenches?

We must determine the number of minutes required for a factory to produce 30,720 wrenches. Call this quantity \(x\). Recall the formula for work: \(\text{work} = \text{rate} \times \text{time}\). We can rearrange this equation to solve for time: \(\text{time} = \text{work} \div \text{rate}\). The problem gives us the amount of work (30,720 wrenches), so if the rate can be determined, the time can also be determined.

Statement 1 says that the factory works at the rate of 32 wrenches per second. This can be converted to wrenches-per-minute (by using the equation 60 seconds = 1 minute). However, we do not need to go any further. Since we CAN find the rate in wrenches per minute, and since we already have the amount of work (i.e. the number of wrenches), we can solve for the time in minutes. Statement 1 alone is sufficient to answer the question. Eliminate answer choices B, C, and E. The correct answer choice is either A or D.

Statement 2 introduces a new quantity: the time necessary to load the wrenches into trucks. Call this quantity \(y\). We want to translate all this information very carefully. Notice that there are actually two equations given. The first is from the fact that it takes 4 times as long to produce the wrenches as it takes to load them into trucks: \(4y = x\), or \(y = 0.25x\). The second equation is from the fact that the time required both to produce the wrenches and to load them is 20 minutes: \(x + y = 20\). This system of equations can be solved by substitution. Substitute \(0.25x\) for \(y\) in the second equation: \(x + 0.25x = 20\). This is a single variable equation and so can be solved for \(x\), the quantity that the prompt asks for. So, Statement 2 is also sufficient.

Answer: D.
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If a certain factory makes a total of 30,720 wrenches, how many minute 29 May 2017, 11:13
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Bunuel
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Tough and Tricky questions: Word Problems.



If a certain factory makes a total of 30,720 wrenches, how many minutes does the factory take to make the wrenches?

(1) The factory creates the wrenches without interruption at a rate of 32 wrenches per second.

(2) It takes 4 times as long for the factory to create the wrenches as it does to load them into trucks, and it takes the factory a total of 20 minutes to do both.

Kudos for a correct solution.

Official Solution:

If a certain factory makes a total of 30,720 wrenches, how many minutes does the factory take to make the wrenches?

We must determine the number of minutes required for a factory to produce 30,720 wrenches. Call this quantity \(x\). Recall the formula for work: \(\text{work} = \text{rate} \times \text{time}\). We can rearrange this equation to solve for time: \(\text{time} = \text{work} \div \text{rate}\). The problem gives us the amount of work (30,720 wrenches), so if the rate can be determined, the time can also be determined.

Statement 1 says that the factory works at the rate of 32 wrenches per second. This can be converted to wrenches-per-minute (by using the equation 60 seconds = 1 minute). However, we do not need to go any further. Since we CAN find the rate in wrenches per minute, and since we already have the amount of work (i.e. the number of wrenches), we can solve for the time in minutes. Statement 1 alone is sufficient to answer the question. Eliminate answer choices B, C, and E. The correct answer choice is either A or D.

Statement 2 introduces a new quantity: the time necessary to load the wrenches into trucks. Call this quantity \(y\). We want to translate all this information very carefully. Notice that there are actually two equations given. The first is from the fact that it takes 4 times as long to produce the wrenches as it takes to load them into trucks: \(4y = x\), or \(y = 0.25x\). The second equation is from the fact that the time required both to produce the wrenches and to load them is 20 minutes: \(x + y = 20\). This system of equations can be solved by substitution. Substitute \(0.25x\) for \(y\) in the second equation: \(x + 0.25x = 20\). This is a single variable equation and so can be solved for \(x\), the quantity that the prompt asks for. So, Statement 2 is also sufficient.

Answer: D.
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From statement 2,we can get value of X=16min,but we dont know the count of wrenches produced in 16mins,so D should be insufficient right?
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If a certain factory makes a total of 30,720 wrenches, how many minute 30 May 2018, 22:04
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