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a jar contains 8 red marbles number one to eight and 12 blue marbles number 1 to 12 find the following probability round solution at 3 decimal place a marble is chosen at random if you're told the marble is red what is the probability that has the number 2 on it

User Ryan Muller
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SOLUTION:

If a marble is chosen at random and we are told the marble is red what is the probability that has the number 2 on it;

We have only one red marble out of eight red marbles that have number two on it.


P\text{ (2/red) = }(1)/(8)\text{ = 0.125 (3 d.p)}

(b) If the first marble is replaced, and another marble is chosen at random if we are told that the marble has number 1 on it, what is the probability that the marble is red;

We have two marbles having 1 (i.e one blue and one red)


P(\text{red/1) = }(1)/(2)\text{ = 0.5 or 0.500 (3 d.p)}

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User CompEcon
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