# Probability distributions

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#1
A fair five-sided spinner is spun(2 red, 1 yellow, 2 blue)Given that the spinner is spun 5 times, write down, in table form, the probability distributions of the following random variables:

a)X, the number of times red appears.
b)Y, the number of times yellow appears.How do you solve this???

Last edited by Niki.gv; 1 year ago
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1 year ago
#2
(Original post by Niki.gv)
A fair five-sided spinner is spun(2 red, 1 yellow, 2 blue)Given that the spinner is spun 5 times, write down, in table form, the probability distributions of the following random variables:

a)X, the number of times red appears.
b)Y, the number of times yellow appears.How do you solve this???

If you spin the spinner 5 times, how many times might it be red on top? Simply list the different numbers.
To get the probabilities, have you covered the binomial distribution?
Last edited by mqb2766; 1 year ago
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#3
(Original post by mqb2766)
If you spin the spinner 5 times, how many times might it be red on top? Simply list the different numbers.
To get the probabilities, have you covered the binomial distribution?
you need to answer it in a table form. And i don't understand why have they used powers and multiplied by 5 and 10. I have attached a pic of the answer, how do you get that? which formula have they used? this question is not from the binomial distribution topic.
Last edited by Niki.gv; 1 year ago
0
1 year ago
#4
(Original post by Niki.gv)
you need to answer it in a table form. And i don't understand why have they used powers and multiplied by 5 and 10. I have attached a pic of the answer, how do you get that? which formula have they used? this question is not from the binomial distribution topic.
You can get 0..5 for red (a). What is the probability of getting / not getting a red? This is a binomial distribution.
The 5 and 10 ... multipliers are the nCr values and refer to the number of different ways of getting r red values. Again, this is central to the binomial distribution.

You could do the question without using the binomial distribution, but it's more work and you're just recreating the binomial distribution. Also, your calculator may have a binomial function to calculate those values directly.
Last edited by mqb2766; 1 year ago
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