A certain drug is made from only two ingredients: compound A and compound B. There are 5 milliliters of compound A used for every 3 milliliters of compound B. If a chemist wants to make 656 milliliters of the drug, how many milliliters of compound A are needed?
Question
Answer: 410 mL
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Explanation:
The ratio of A to B is 5:3
Multiply both parts by x to get 5x:3x
We need 5x parts of A and 3x parts of B
Adding those parts should get us 656 mL total
A+B = total
5x+3x = 656
8x = 656
x = 656/8
x = 82
Therefore, we need 5x = 5*82 = 410 mL of compound A
Also, we need 3x = 3*82 = 246 mL of compound B
In total, we have A+B = 410+246 = 656 mL which helps confirm the answer.
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Side note: The ratio 410:246 reduces to 5:3 after dividing both parts by 82.