Question 1200461:  A store purchases baseball hats from three different manufacturers. In manufacturer A's box, there are 12 blue hats, 6 red hats, and 6 green hats. In manufacturer B's box, there are 10 blue hats, 10 red hats, and 4 green hats. In manufacturer C 's box, there are 8 blue hats, 8 red hats, and 8 green hats. A box is selected at random, and a hat is selected at random from that box. If the hat is red, find the probability that it came from manufacturer A's box. 
 
 Answer by ikleyn(52903)      (Show Source): 
You can  put this solution on YOUR website! . 
A store purchases baseball hats from three different manufacturers.  
In manufacturer A's box, there are 12 blue hats, 6 red hats, and 6 green hats.  
In manufacturer B's box, there are 10 blue hats, 10 red hats, and 4 green hats.  
In manufacturer C 's box, there are 8 blue hats, 8 red hats, and 8 green hats.  
A box is selected at random, and a hat is selected at random from that box.  
If the hat is red, find the probability that it came from manufacturer A's box. 
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            This problem is on conditional probability.
 
 
 
They want you find the probability that a red hat is from box A given that
it is red, P(red hat is from box A | the hat is red).
This probability is the ratio
    P(red hat is from box A | the hat is red) =  .  (*)
The numerator is
    P(red hat is from box A) =   =   =  .
The denominator is 
    P(the_hat_is_red) =   = 
                      =   =   =  .
Therefore, the final probability (*) is
    P(red hat is from box A | the hat is red) =   =   =  .    ANSWER
 
Solved.
 
 
 
 
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