When is one candle twice the height of the other?
Two candles are the same height. The first burns steadily and lasts 6 hours; the second is thinner, burns steadily and lasts 4 hours. Both are lit at the same moment.
After how many hours is the first candle exactly twice as tall as the second?
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Write the height of each candle as a fraction of its starting height after t hours. Set one equal to twice the other.
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