Two cylindrical candles of the same height but different diameters are lit at the same time. The
first is consumed in 4 hours and the second in 3 hours. Assuming that they burn at a constant
rate, how long after being lit was the first candle twice the height of the second candle?  Select.
A) 1 hr	B) 1 hr 12 min	C) 2 hr	D) 2 hr 12 min	E) 2 hr 24 min
Assume each candle is 1 unit high. Since the burn rates are 1/3 and 1/4 units   per hour, after t hours they have been consumed by an amount of t/3 and t/4. We want   1- t=4 = 2(1 - t=3). This occurs when t = 2.4 = 2*24/60 hrs.   correct answer 2 hr 24 min
<result>E</result>
Two cylindrical candles of the same height but different diameters are lit at the same time. The
first is consumed in 4 hours and the second in 3 hours. Assuming that they burn at a constant
rate, how long after being lit was the first candle twice the height of the second candle?