The answers are correct. Look at their sum. It is one as it should be.View attachment 20863
I am confused about part (a). I apologise firstly for bombarding you with Q this week. I think the answers are wrong but i am really not sure how they have derived it as three GGG (no blue) should be (1/2)^3, as there are 3 B and 6 G. I am confused.
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They way they have explained it it looks like they used the three options. Sorry I was thinking of something else. I obviously need to take a break and look at this again. Simpler than i thought.No blue means the same thing as three green. There are six green balls out of nine total.
[MATH]\dfrac{6}{9} * \dfrac{6}{9} * \dfrac{6}{9} = \left ( \dfrac{2}{3} \right )^3 = \dfrac{8}{27}.[/MATH]
Where do you get (1/2)? It is not equally likely to draw a blue ball and green ball.
First, incorrect probabilities can add up to one. If they are correct, they add to one. You cannot deduce from that that if they add to one, they are correct.The answers are correct. Look at their sum. It is one as it should be.
Is my statement incorrect? If not why are you butting in?First, incorrect probabilities can add up to one. If they are correct, they add to one. You cannot deduce from that that if they add to one, they are correct. Second, the question asserts that the probabilities given are wrong. We need to explain why they are right.
A Because you did not address the actual question, which was why (1/2) was not used.Is my statement incorrect? If not why are you butting in?
True. It is a good check, not a proof.Lol. I do like there is merit in method of checking that Pka has mentioned. Its useful as a way of checking especially in an exam.