A bag contains 4 identical red balls and 3 identical black balls. The experiment consists of drawing one ball, then putting it into the bag and again drawing a ball. What are the possible outcomes of the experiment?

Explanation

A bag contain 4 red balls and 3 black balls

Let us assumed Red = R

Let us assume black = B

Now, a ball drawn is first attempt, so elementary event is
S1​={R,B}


And, the bag will put into the bag and draw again, then the elementary events are
S2​={R,B}

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