Question: Pipe A can fill a Tank in 18 Hours, Pipe B can empty a Tank in 12 Hours, Pipe C can fill Tank in 6 Hours. The Tank is already filled up to 1/6 of its capacity. Now Pipe A is opened in the First Hour alone, Pipe B is opened in the Second Hour alone and Pipe C is opened in the Third Hour alone. This cycle is repeated until the Tank gets filled. Then in How many Hours does the rest of Tank gets filled?

A. 15 Hours
B. 18 Hours
C. 20 Hours
D. 24 Hours
E. None

Answer: B

Solution and Explanation:

Approach Solution 1:
To answer this GMAT question, apply the data provided in the question. These issues pertain to many different branches of mathematics. This query relates to algebra. Because of how the options are set up, it is hard to choose the best one. Applicants must be able to understand the proper strategy for getting the desired response. There is only one correct answer out of the five options offered.
A would pump in 2 units, B would pump out 3 units, and C would pump in 6 units every hour, for a total of 5 units added in one cycle of 3 hours if the total work was 36 units (a common multiple for 18, 12, and 6).
Six units are already present because 1/6 is already full.
At 0 hours: 6 units after 3 hours (1 cycle) are equal to 6 + (2-3+6) = 6 + 5*(1) = 11
fill the 36 units with:
36 = 6 + 5x, where x is the number of cycles,
and x = 6 represents 3 hours every cycle.
18 hours is the correct answer.

Correct option: B

Approach Solution 2:
To answer this GMAT question, apply the data provided in the question. These issues pertain to many different branches of mathematics. This query relates to algebra. It is challenging to choose the best option due to the way the options are presented. Applicants must be able to understand the proper strategy for getting the desired response. There is only one correct answer out of the five options offered.
Choose a number that is a multiple of 18, 6, and 12. Say 36.
The tank has a 36-unit capacity and is currently 6 units full.
Now that A is taking 12 hours, it is filling a tank of 36 units at a rate of 2 units per hour. Likewise, B is doing a -3 and C is performing a +6.
Together, they add up to +2-3+6, which is +5. There are 30 units left in our capacity. So, we shall repeat this process six times. each time taking three hours. therefore, 18 hours.
Correct option: B

Approach Solution 3:
To answer this GMAT question, apply the data that was provided in the question. These issues pertain to many different branches of mathematics. This query relates to algebra. It is challenging to choose the best option due to the way the options are presented. Applicants must be able to understand the proper strategy for getting the desired response. There is only one correct answer out of the five options offered.
The tank is emptied to around half its capacity: 30/36
30/36- (1/18 - 1/12 + 1/6)=25/36
The tank will fill to 5/6 capacity in 3 hours.
Filling the tank will take 6 x 3 = 18 hours.
Correct option: B

“Pipe A can fill a Tank in 18 Hours, Pipe B can empty a Tank in 12 Hour" - is a topic of the GMAT Quantitative reasoning section of GMAT. This question has been borrowed from the book “GMAT Official Guide Quantitative Review”. To understand GMAT Problem Solving questions, applicants must possess fundamental qualitative skills. Quant tests a candidate's aptitude in reasoning and mathematics. The GMAT Quantitative test's problem-solving phase consists of a question and a list of possible responses. By using mathematics to answer the question, the candidate must select the appropriate response. The problem-solving section of the GMAT Quant topic is made up of very complicated math problems that must be solved by using the right math facts.

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