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VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Mathematical Methods CAS => Topic started by: MrBrillsbury on August 19, 2017, 03:10:11 pm

Title: Question Help
Post by: MrBrillsbury on August 19, 2017, 03:10:11 pm
Sarah has a biased die. When it is rolled, the probability of obtaining a particular outcome (X) is shown in the following table:
x           |  1   |   2  |   3  |  4  |   5  | 6
Pr(X=x) | 0.1 | 0.2 | 0.3 | 0.2 | 0.1 | p

What is the probability that, given that the sum of the rolls is a six, one of the rolls is a three?
Title: Re: Question Help
Post by: Sine on August 19, 2017, 03:19:18 pm
Sarah has a biased die. When it is rolled, the probability of obtaining a particular outcome (X) is shown in the following table:
x           |  1   |   2  |   3  |  4  |   5  | 6
Pr(X=x) | 0.1 | 0.2 | 0.3 | 0.2 | 0.1 | p

What is the probability that, given that the sum of the rolls is a six, one of the rolls is a three?
sum of the probabilities must be 1 so first you should find p
It doesn't say how many rolls but I'll assume 2
Now what we basically need is Pr(one of the rolls is a 3 | sum of the rolls is a six)
This should look familiar now? Hope this helps