In: Statistics and Probability
An economy pack of highlighters contains 12 yellow, 6 blue, 4 green, and 3 orange highlighters. An experiment consists of randomly selecting one of the highlighters and recording its color. Find the probability that a blue or yellow highlighter is selected given that a yellow highlighter is selected.
The probability that a blue or yellow highlighter is selected given that a yellow highlighter is selected.
Given that Yellow highlight is selected, Therefore probability that that a blue or yellow highlighter = 1 because given that selected highlighter is Yellow , then the event of selecting a blue or yellow highlighter is certain.
The probability that a blue or yellow highlighter is selected given that a yellow highlighter is selected = 1
Formula for a conditional probability :
Y : Event of selecting a Yellow highlighter
P(Y) = Probability of selecting a Yellow highlighter
B : Event of selecting a Blue highlighter
P(B) = Probability of selecting a blue highlighter
The probability that a blue or yellow highlighter is selected given that a yellow highlighter is selected = P((Y or B)|Y)
Applying the above formula
(Y or B) and Y = Y
P((Y or B) and Y) = P(Y)
The probability that a blue or yellow highlighter is selected given that a yellow highlighter is selected = 1