SOLUTION: A bag contains 3 red balls and 5 blue balls. One ball is taken at random, its colour noted, and put back into the bag. A second ball is taken at random , and again its colour is no
Algebra ->
Probability-and-statistics
-> SOLUTION: A bag contains 3 red balls and 5 blue balls. One ball is taken at random, its colour noted, and put back into the bag. A second ball is taken at random , and again its colour is no
Log On
Question 334118: A bag contains 3 red balls and 5 blue balls. One ball is taken at random, its colour noted, and put back into the bag. A second ball is taken at random , and again its colour is noted.
What is the probability of obtaining two balls of different colours?
P(different colors) = P[(red first AND blue second) OR (blue first AND red second)]
"AND" means MULTIPLY and "OR" means ADD, so that equals
P[red first] x P[blue second] + P[blue first] x P[red second] =
=
Edwin
