a bowl contains slips of paper numbered 1-9. two slips are drawn, one after the other and without replacement. find the probability of the first number being drawn is greater than 8 and the second number is less than 3
\[\frac{1}{9}\times \frac{2}{8}=\frac{2}{72}=\frac{1}{36}\]
First time you picked, you get to choose from 9 slips and there is only one slip that is greater than 8. 1/9 Second time , you have 8 slips left, and there are 2 slips that is lower than 3 2/8 1/9 * 2/8=
But if the first number you pick is less than three, than the probability of drawing a number less than three the second time is cut in half
That's not the situation the question's asking about.
it has to be taken into account
Are you disputing that the probability of initially picking a number greater than 8 is 1/9 or that the probability of picking a number less than 3 is 2/8?
i am disputing the fact that the second number drawn may or may not be affected by the first draw. if the first draw were to be a 2, then the probability of drawing a number less than three on the second draw would indeed be 1/8 not 2/8
You are absolutely correct, but if the first number picked was a 2 then the probability of the first number being greater than 8 is zero, so this doesn't affect the question.
ah i see now thank you. wanna take a shot another probability question?
Go for it, quick though, I need to go out in a min.
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