Question

Solution a is made up of alcohol and water mixed in the ratio of 21:4 by volume; solution b is made up of alcohol and water mixed in the ratio of 2:3 by volume. If solution a and solution b are mixed in the ratio of 5:6 by volume, what percent of the resultant mixture is alcohol?

Answer 1

• Since the question asks us to find the percent of alcohol in the mixture. It would be best if we convert everything in percentage and then solve it quickly.

• If we take Alcohol, then 

o Percentage of Alcohol in Solution A =21∗10025=84=21∗10025=84%

o Percentage of Alcohol in Solution B =2∗1005=40=2∗1005=40%

• Since the ratio of Solution A: Solution B =5:6=5:6

• The Percentage of Alcohol in the mixture =(5∗84+6∗40)(5+6)=(5∗84+6∗40)(5+6)

=66011=66011%

=60=60%

Thus, the correct answer is Option C.