Question

You are given four balls. 2 red and 2 blue. You are asked to draw one ball each time from the box. Before your draw, you need to guess what you would get?

Answer 1

Answer:

At every pick the probability may vary depending upon your guess is right or wrong.

Step-by-step explanation:

First pick:

Equal probability for both red and blue = 1/2

Second pick:

case 1: If first pick was red.

then predict blue because the probability of blue exceeds the probability of red.

P(b) = 2/3

P(r) = 1/3

case 2: if first pick was blue.

then predict red because the probability of red exceeds the probability of blue.

P(r) = 2/3

P(b) = 1/3

Third pick:

case 1: R,B

then predict either red or blue due to equal probabilities.

note: Similar case for B,R.

case 2: RR

then obviously you will predict blue because P(b)=1  and vice versa for the case if the first two draws were BB.

Fourth Pick:

Fourth pick would be obvious because you are left with only remaining colored ball for which the probability must be 1.