<PRE><B>Question 1115908</B>
a pharmacist needs to make a 1% hydrocortisone cream. How many grams of 2.5% hydrocortisone should be added to 15 grams of cream base (0% hydrocortisone) to make the 1% cream? 
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Equation::
hydro + hydro = hydro
0.025x + 0*15 = 0.01(x+15)
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0.025x = 0.010x + 0.15
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25x - 10x = 150
15x = 150
x = 10 g (amt. of 2.5% cream needed)
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Cheers,
Stan H.
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