Question

You need 560 mL of a 70% alcohol olution. On hand, you have a 80% alcohol mixture. How much of the 80% alcohol mixture and pure water will you need to obtain the deired olution?

Answer 1

Below

Explanation:

x = amount of 80% to use

amount of alcohol in ingredients = amount of alcohol in final product

.8 x = .7 (560)

x = 490 ml