One liter of 70% alcohol is needed. How much 95% alcohol is required to make the 70% solution. And thank you for last question and any future ones.

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To determine the amount of 95% alcohol required to make a 70% solution, we can use the concept of dilution.

Let's assume x liters of 95% alcohol are needed to make the 70% solution.

In the 70% alcohol solution, the amount of pure alcohol is 70% of 1 liter, which is 0.7 liters.

Similarly, in the x liters of 95% alcohol, the amount of pure alcohol is 95% of x liters, which is 0.95x liters.

We can set up an equation based on the total amount of alcohol in the solution:

0.7 = 0.95x

To solve for x, divide both sides of the equation by 0.95:

x = 0.7 / 0.95

Using a calculator, we find that x is approximately 0.737 liters.

Therefore, approximately 0.737 liters of 95% alcohol is required to make a 70% solution using 1 liter of 70% alcohol.