Probability of picking a red ball

There are 7 balls in a bag. 3 of them are red, and 4 are blue. Your friend randomly removes one of the balls from the bag, but doesn't tell you its color. He asks you to also randomly chose a ball from the bag. What is the probability that you will pick a red ball?

Answer

Answers can be viewed only if
  1. The questioner was satisfied and accepted the answer, or
  2. The answer was disputed, but the judge evaluated it as 100% correct.
View the answer
The answer is accepted.