To gain entry to the Incredibly Super Smart Genius Club (with a free membership
ID: 3023430 • Letter: T
Question
To gain entry to the Incredibly Super Smart Genius Club (with a free membership badge!), you are asked to solve the following set of questions. (We know you are already Incredibly Smart, but this club has to have something to pass the time (-: ) Before you is an urn with three types of colored marbles: Red, White, and Blue. You are told that there are 10 Red marbles, 5 White marbles, and 5 Blue Marbles in the urn at the start. In the follow set of questions, we use the abbreviations: R = Red; W = White; B = Blue. Suppose we have the following counts for numbers of marbles drawn so far: R Marbles = 3; W Marbles = 3; B Marbles = 1. What is the probability of drawing a W marble on draw 8? (1 point) What is the probability of drawing a R marble on draw 9 if a W marble was selected on draw 8? (2 points) What is the probability of drawing a R marble on draw 9 if an R colored marble was selected on draw 8? (2 points)
Explanation / Answer
Given : Marbles, R=10 ; W =5; B =5
Suppose we have the following counts for numbers of marbles drawn so far: R Marbles = 3; W Marbles = 3; B Marbles = 1. The probability of drawing a W marble on draw 8 is = 2/13
The probability of drawing a R marble on draw 9 if a W marble was selected on draw 8 = 7/12
The probability of drawing a R marble on draw 9 if an R colored marble was selected on draw 8 =6/12