A cistern has a leak which would empty the cistern in 20 minutes. A tap is turned on which admits 2 liters a minute into the cistern, and it is emptied in 24 minutes. How many liters does the cistern hold?
Choose the correct choice from the following choices: A) 480 B) 240 C) 289 D) 270 E) 927
1/x - 1/20 = -1/24   x = 120   120 * 2= 
<gadget id="calculator">120 * 2</gadget>
<output>240</output>
240   Answer: 240
<result>B</result>
A cistern has a leak which would empty the cistern in 20 minutes. A tap is turned on which admits 2 liters a minute into the cistern, and it is emptied in 24 minutes. How many liters does the cistern hold?