Word Problems Practice Test

A chemist has two solutions: Solution A is $20\%$ acid and Solution B is $50\%$ acid.

How many milliliters of Solution A must be mixed with 40 milliliters of Solution B to obtain a mixture that is $30\%$ acid?

A car rental company charges a flat base fee of \$30 plus \$0.15 for every mile driven. If a customer's total rental cost (before taxes) is \$63, how many miles did the customer drive?