A spinner has 3 sectors
coloured red, blue,
and yellow. The pointer on the spinner is spun 3 times. Find the
probability of each event:
a) red, blue, and yellow


b) blue, blue, and not red


c) blue, blue, and blue


im having a lot of trouble with this :(

 Jan 6, 2021

a) 1/3*1/3*1/3=1/27

b) 1/3*1/3*2/3=2/27

c) 1/3*1/3*1/3=1/27


 Jan 6, 2021

That's what I did and the answer key said it was wrong :/

Kadjaye  Jan 6, 2021
edited by Kadjaye  Jan 6, 2021

Very close, pay attention to how it does not specify the order in which the three spins have to happen. For example:


a) asks for red, blue, and yellow... but it does not have to be in that order. There is a 1/3 chance for each color to be landed on... so there is a 1/27 chance that in that order, will be the outcome.


But, since it could also be blue, red, and yellow or yellow, red, and blue. We have to account for that as well.


There are 3*2*1 different combinations. Therefore your answer is 6/27 or 2/9. (for part a)


See if you can do the rest :D..




Also, I can't say that I am always right, so if you think I made a mistake, just let me know :)

 Jan 6, 2021

yea... i shouldnt have made the assumption of order. thanks

AvenJohn  Jan 6, 2021

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