Question 1056038
An order is written for 15 grams of a 5% lidocaine topical cream. Only 3% concentration and 6% concentration are available. How much of the 3% concentration must be added to the 6% concentration to fill this order? 
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t = amount of 3%
s = amount of 6%
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t + s = 15
3t + 6s = 15*5