Question

a certain drug is made from only two ingredients: compound A and comppund B. There are 5 milliliters of compound A used for every 4 milliliters of compound B. if a chemist wants to make 477 milliliters of the drug, how many milliliters of compound A are needed?

Answer 1

4:5 is the same as 4x:5x where 4x is compound A and 5x is compound B.
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Solve for "x":
If amount of compound A is 4x = 477
x = 477/4
Then amt of compound B is 5x = 5(477/4) = 596.25 ml