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A tank can be filled by a tap in 8 hrs while it can be emptied by another tap in 18 hrs. if both the taps are opened simultaneously, then after how much time will the cistern get filled? A) 14hrs 24mins B) 14 hrs 12 mins C) 14hrs 56 mins D) 14hrs 30mins

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A tank can be filled by a tap in 8 hrs while it can be emptied by another tap in 18 hrs. if both the taps are opened simultaneously, then after how much time will the cistern get filled? A) 14hrs 24mins B) 14 hrs 12 mins C) 14hrs 56 mins D) 14hrs 30mins
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A

Net part filled in 1hr = (1/8 – 1/18)

= 9 – 4/72

= 5/72

Therefore the tank will be filled in 72/5 hrs i.e., 14 hrs 24mins
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