Question 1158630
A guess might be that the dropped units for the concentration of cortisone cream is  "percent".


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How many grams of 1<b>%</b> hydrocortisone cream and 5<b>%</b> hydrocortisone cream are needed to prepare 60 grams of 2.5%,...
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Using v for how much of the 5%, and 60-v for the 1%:


{{{1(60-v)+5v=2.5*60}}}

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{{{60-v+5v=2.5*60}}}

{{{(5-1)v=2.5*60-1*60}}}

{{{highlight_green(v=60((2.5-1)/(5-1)))}}}, and from here you can do the rest.