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Question
Choose the most appropriate option
Taps ‘A’ and ‘B’ can fill a tank in `37 1/2` minutes and 45 minutes respectively. Both taps are opened and after some time tap ‘B’ is turned off. The tank is filled completely in exactly 30 minutes, if tap ‘B’ is turned off after:
Options
12 minutes
15 minutes
9 minutes
10 minutes
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Solution
9 minutes
Explanation:
By shortcut method,
Pipe B should be closed after`=(1-(30xx2) /75) xx 45`
`=15/75xx45`
= 9 minutes.
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