In equation form we multiply their individual mixing rates by the time t to get:

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Factor the t out on the left side:

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Putting all the numbers in the parentheses over the common denominator of 3 results in:

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Combine all the fractions by adding their numerators and placing them over the common

denominator of 3 to get:

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Solve this problem by dividing both sides by . On the left side this just leaves

t. On the right side, recall the rule that dividing by a fraction is the same as multiplying

by its inverse. Therefore, the right side can be determined by multiplying:

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Take your calculator and divide 30 by ll to find that . So the answer

is minutes. And 0.727 times 60 seconds is about 43.6 seconds. So the answer to

this problem is t = 2 minutes and 43.6 seconds.