Randy'sbar serves customers every weeknight from 4 pm to 1 am. In Randy's bar,Silvermoonbeer is sold at a constant rate except during happy hour, from 6:30 to 7:30 pm, when the rate triples.
If a keg of Silvermoon beer is half empty at 5pm on Monday, and two-thirds empty at the beginning of the happy hour, when will it be completely empty?  Options: A) Monday, 7:30 pm B) Monday, 9 pm C) Monday, 7 pm D) Monday, 6:45 pm E) Monday, 9:30 pm
Let the keg be a 150 Litre keg   At 5 pm.. There are 75 litres   At 6:30 pm there are 50 litres.   So, consumption rate is 25 litres per 1.5 hours.   So it will take 3 hours to finish 50 litres at this rate.   During happy hour it sells 3 times faster. So, rate = 1 hour per 50 litres.   So, keg becomes empty at 6:30 + 1 hour = 7 pm   Answer is Monday, 7 pm
<result>C</result>
Randy'sbar serves customers every weeknight from 4 pm to 1 am. In Randy's bar,Silvermoonbeer is sold at a constant rate except during happy hour, from 6:30 to 7:30 pm, when the rate triples.
If a keg of Silvermoon beer is half empty at 5pm on Monday, and two-thirds empty at the beginning of the happy hour, when will it be completely empty?