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The total volume must be 20 cc. Therefore
?This is equation (1).
The quantity of the medicine in cc of the first solution is .
The quantity of the medicine in cc of the second solution is .
The total quantity of medicine in the mixture is therefore ... ?
This must be 6% of the total volume, cc, which is ?
The second equation is therefore
?This is equation (2).
Can you complete what I have started, and then solve the simultaneous equations to find and ?