Question

An urn contains 10 red balls, 20 yellow balls, and 40 orange balls. If you reach into the urn and select a single ball at random, what is the probability of selecting a red ball? State your answer as a fraction.

Answer 1

From the problem, there are 10 red balls, 20 yellow balls and 40 orange balls.

The probability of selecting a red ball is the number of red balls divided by the total number of balls :

$\begin{gathered} p=\frac{10}{10+20+40}=\frac{10}{70} \\ p=\frac{1}{7} \end{gathered}$

The answer is 1/7