Question

A mixture of $30$ liters of paint is $25\%$ red tint, $30\%$ yellow tint and $45\%$ water. Five liters of yellow tint are added to the original mixture. What is the percent of yellow tint in the new mixture?

$25$

$35$

$40$

$45$

$50$

Solution:

The amount of yellow tint in the original mixture is $.3 \times 30 = 9$ liters. Adding $5$ liters results in a total of $14$ liters of yellow tint.

The new mixture has a total of $35$ liters, so the percent of yellow tint is $100 \cdot \dfrac{14}{35} = 100 \cdot \dfrac{2}{5} = 40 \%.$

Thus, C is the correct answer.

2007 AMC 8 Problem 17

Solution:

Problem 17 in Other Years