I need the solution to this question ASAP.

A box contains 2 black balls, 4 red balls and 6 green balls. First one ball is

randomly taken out from the box and is kept out. After that a second ball is taken

out. Find

a) The probability that both the balls are red.

b) The probability that at least one will be black.

Here is the answer to your question.
Total number of balls = 12
Let A: the event of drawing red ball in 1st draw
B: the event of drawing red ball in 2nd draw

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Thank You so much for answering my query. Though I had already managed to figure it out.

1). (4C2)/(12C2)

2).1 - (10C2)/(12C2)

I did it by Combination and got the correct answers.

This how I believe NCERT wanted the answer to be.

But never the less Thank You once again for your detailed and prompt reply.

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