THe following question is taken from one of the study manuals.

An urn contains 4 red balls, 8 green balls, and 2 yellow balls. Five balls are randomly selected, with replacement, from the urn. What is the probability that 1 red ball, 2 green balls and 2 yellow balls will be selected.

The choices were: (a) 3/512, (b) 192/7^5, (c) 15/512 (d) 8/143 (e) 960/7^5

MY answer was: (4C1)(8C2)(2C2)/14^5. However, my answer did not match. Could you tell me what I have done wrong?

HOw would this answer change if the question was sampling with replacement?

Thank you.

An urn contains 4 red balls, 8 green balls, and 2 yellow balls. Five balls are randomly selected, with replacement, from the urn. What is the probability that 1 red ball, 2 green balls and 2 yellow balls will be selected.

The choices were: (a) 3/512, (b) 192/7^5, (c) 15/512 (d) 8/143 (e) 960/7^5

MY answer was: (4C1)(8C2)(2C2)/14^5. However, my answer did not match. Could you tell me what I have done wrong?

HOw would this answer change if the question was sampling with replacement?

Thank you.

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