Question 1032050
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Two candles of equal length are lit at the same time. One candle take 6 hours to burn out, the other takes 9 hours to burn out. 
After how much time will the slower burning candle be exactly twice as long as the faster burning candle?
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The equation which describes the situation is

{{{2*(1-t/6)}}} = {{{1-t/9}}}.   (1)

{{{t/6}}} is the rate for the first candle, and {{{1/9}}} is the rate for the second candle.

After solving (1) you get t = 4.5 hours = {{{4}}}{{{1/2}}} of an hour.

The remaining parts at this moment will be {{{1/4}}} for the faster candle and {{{1/2}}} for the slower candle.
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