Question

A bag contains 6 red marbles, 10 green marbles, and 4 yellow marbles. You randomly pick a marble. What is the probability that it is a red or yellow? Write your answer as a reduced fraction (numerator/denominator).

Answer 1

Red marbles = 6

Green marbles = 10

Yellow marbles = 4

Total marbles in the bag = 20

The probability of picking a red or a yellow marble is;

`\begin{gathered} Pr(\text{red or yellow)=Pr(picking red)}+Pr(\text{ picking yellow)} \\ Pr(\text{ picking red) = }\frac{n(red\text{ marbles)}}{total\text{ marbles}} \\ Pr(\text{ picking red) =}(6)/(20) \\ Pr(\text{ picking yellow)=}(4)/(20) \end{gathered}`
`\begin{gathered} Pr(\text{ picking red or yellow)=}(6)/(20)+(4)/(20)=(10)/(20) \\ Pr(\text{ picking red or yellow)=}(1)/(2) \end{gathered}`

The probability of picking a red or yellow marble is 1/2