Pipes A and B can fill a tank in 16 hours and 24 hours, respectively, whereas pipe C alone can empty the full tank in x hours. When all the 3 pipes ar - Quantitative Aptitude MCQ Competitive Exam 2026 | ExamTest.live

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Pipes A and B can fill a tank in 16 hours and 24 hours, respectively, whereas pipe C alone can empty the full tank in x hours. When all the 3 pipes are opened together, the tank is full in 20 \frac{4}{7} hours. What is the value of x ?

Solution & Step-by-step Explanation

Total time when all 3 pipes are working together = 20 \frac{4}{7} = \frac{144}{7} hours.According to the question, the work done per hour is: \frac{1}{16} + \frac{1}{24} - \frac{1}{x} = \frac{7}{144} Rearranging to solve for \frac{1}{x} : \frac{1}{x} = \frac{1}{16} + \frac{1}{24} - \frac{7}{144} Finding the LCM of 16, 24, and 144, which is 144 : \frac{1}{x} = \frac{9 + 6 - 7}{144} \frac{1}{x} = \frac{8}{144} \frac{1}{x} = \frac{1}{18} x = 18

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Pipes A and B can fill a tank in 16 hours and 24 hours, respectively, whereas pipe C alone can empty the full tank in x hours. When all the 3 pipes are opened together, the tank is full in 20 \frac{4}{7} hours. What is the value of x ?

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