SOLUTION: A certain drug is made from only two ingredients: compound A and compound B. There are 5 milliliters of compound A used for every 4 milliliters of compound B. If a chemist wa

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Question 1141418: A certain drug is made from only two ingredients: compound A and compound B. There are
5 milliliters of compound A used for every
4 milliliters of compound B. If a chemist wants to make
468 milliliters of the drug, how many milliliters of compound B are needed?

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
[ quantity of B ] / [ quantity of A ] = 4/5
also
[ quantity of B ] / [ quantity of A + B ] = 4/9
so, I can say
+4%2F9+=+x+%2F+468+ ( x will be in ml )
+4%2A468+=+9x+
+9x+=+1872+
+x+=+208+
208 ml of B are needed
------------------------------
check:
+4%2F5+=+208+%2F+%28+468+-+208+%29+
+4%2F5+=+208+%2F+260+
+4%2A260+=+5%2A208+
+1040+=+1040+
OK