Solute weight+solvent weight = solution weight.

The weight of solute/solution × 100% = concentration.

Solution weight × concentration = solute weight

Solute weight-concentration = solution weight.

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Fill the potion-pour x liters-fill it with water-pour x liters-fill it with water.

A B C D E

The pure liquid medicine in B is (63-x) liters, and the concentration of pure liquid medicine in C is ((63-x)/63) times 100%. D is the same as e (pure medicine), use X.

Means ((63-x)? /63)