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A box contains 5 white balls, 2 black balls and 3 red balls of the same Size .A ball is selected at random from the box and then replaced .A second ball is the selected. find the probability of obtaining (a) Two red balls (b) Two white balls or two black balls. (2) One black ball and one red ball.​

User Slashroot
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Explanation:

The probability of selecting one red ball from the box is 3/10.

Since the ball is replaced, the probability of selecting another red ball is also 3/10.

Therefore, the probability of obtaining two red balls is (3/10) * (3/10) = 9/100 or 0.09.

The probability of obtaining two white balls or two black balls is calculated as follows:

The probability of selecting one white ball from the box is 5/10.

Since the ball is replaced, the probability of selecting another white ball is also 5/10.

Therefore, the probability of obtaining two white balls is (5/10) * (5/10) = 25/100 or 0.25.

Similarly, the probability of obtaining two black balls is also 0.25.

The probability of obtaining one black ball and one red ball is calculated as follows:

The probability of selecting one black ball from the box is 2/10.

The probability of selecting one red ball from the box is 3/10.

Since the ball is replaced, the probability of selecting another ball that’s either black or red is (2/10 + 3/10) = 5/10.

Therefore, the probability of obtaining one black ball and one red ball is (2/10) * (3/10) * (5/10) * 2 = 6/100 or 0.06.

User Jshepherd
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