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- Find each pipe's rate.
- Add filling rates and subtract emptying rates.
- Invert the net rate to get time.
Correct Answer: A
Correct Answer: A
Method / Topic: Pipes and Cisterns
The answer uses the net filling rate.
Short Explanation
Detailed Explanation
Correct Answer: A
Method / Topic: Pipes and Cisterns
<table cellspacing="0" style="border-collapse:collapse; height:20px; width:85px">
<tbody>
<tr>
<td style="border-bottom:none; border-left:none; border-right:none; border-top:none; height:20px; vertical-align:top; white-space:normal; width:85px"><span style="color:#000000">Add both inlet rates and subtract the outlet rate. The net rate is 1/9 tank per hour, so time is 9 hours.</span></td>
</tr>
</tbody>
</table>
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Learn + Solve: Shortcut, Trap & Fast Route Click to view shortcut, steps, and common mistake
Shortcut used, common trap, and the fastest solving route
- Find each pipe's rate.
- Add filling rates and subtract emptying rates.
- Invert the net rate to get time.
Two inlet pipes fill a tank in 12 hours and 18 hours, while an outlet empties it in 36 hours. How long will the tank take to fill when all three are open?
Explanation
Correct Answer: A
Method / Topic: Pipes and Cisterns
The answer uses the net filling rate.
Short Explanation
Detailed Explanation
Correct Answer: A
Method / Topic: Pipes and Cisterns
<table cellspacing="0" style="border-collapse:collapse; height:20px; width:85px">
<tbody>
<tr>
<td style="border-bottom:none; border-left:none; border-right:none; border-top:none; height:20px; vertical-align:top; white-space:normal; width:85px"><span style="color:#000000">Add both inlet rates and subtract the outlet rate. The net rate is 1/9 tank per hour, so time is 9 hours.</span></td>
</tr>
</tbody>
</table>
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