Question
A pipe fills a tank in $6$ hours and another pipe empties it in $9$ hours. If both are opened together, in how many hours will the empty tank fill? / एक पाइप एक टंकी को $6$ घंटे में भरता है और दूसरा पाइप उसे $9$ घंटे में खाली करता है। यदि दोनों एक साथ खोले जाएँ, तो खाली टंकी कितने घंटे में भरेगी?
Option 3 : $18$ hours / $18$ घंटे
Detailed Solution
सही उत्तर $18$ hours / $18$ घंटे है।
Net rate $= \frac{1}{6} - \frac{1}{9} = \frac{1}{18}$, so the tank fills in $18$ hours. / शुद्ध दर $= \frac{1}{6} - \frac{1}{9} = \frac{1}{18}$, अतः टंकी $18$ घंटे में भरेगी।
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prepsnap.in • Numerical AbilityQuestion:
A pipe fills a tank in $6$ hours and another pipe empties it in $9$ hours. If both are opened together, in how many hours will the empty tank fill? / एक पाइप एक टंकी को $6$ घंटे में भरता है और दूसरा पाइप उसे $9$ घंटे में खाली करता है। यदि दोनों एक साथ खोले जाएँ, तो खाली टंकी कितने घंटे में भरेगी?
Correct Answer: $18$ hours / $18$ घंटे
Net rate $= \frac{1}{6} - \frac{1}{9} = \frac{1}{18}$, so the tank fills in $18$ hours. / शुद्ध दर $= \frac{1}{6} - \frac{1}{9} = \frac{1}{18}$, अतः टंकी $18$ घंटे में भरेगी।