1. The problem asks for the total amount of dextrose in grams in 250 ml of a 70% (w/v) dextrose solution. 2. The formula for weight/volume percent concentration is: $$\text{Concentration (\% w/v)} = \frac{\text{mass of solute (g)}}{\text{volume of solution (ml)}} \times 100$$ 3. Rearranging to find the mass of solute: $$\text{mass of solute (g)} = \frac{\text{Concentration (\% w/v)} \times \text{volume of solution (ml)}}{100}$$ 4. Substitute the given values: $$\text{mass of dextrose} = \frac{70 \times 250}{100}$$ 5. Calculate: $$\text{mass of dextrose} = \frac{17500}{100} = 175$$ 6. Therefore, the total amount of dextrose in the final preparation is 175 grams.