Question 510774:  I saw this problem: 
At Joe's Restaurant, one-fourth of the patrons are male and one-fifth of the patrons are from out of town. What proportion would you expect to be male and out of town?  
Someone answered it this problem like this: 
For this kind of problem, you mulitply the two fractions.  So 1/4 x 1/5 = 1/20.  We would expect 1/20 of the patrons to be both male and from out of town.
 
Here is a way to visualize this.
 
    In Town Out of Town Total 
Male       4         1                     5 
Female     12        3                   15 
Total      16        4                   20
 
Imagine that there are 20 people in the restaurant.  Five are male (so 5/20 = 1/4) and 4 are from out of town (so 4/20 = 1/5).  One way to show this is with the chart above.  Only 1 person (1/20) is both male and from out of town.
 
My question is: 
What is the reasoning behind the sentences below????  I don't understand that.   
For this kind of problem, you mulitply the two fractions.  So 1/4 x 1/5 = 1/20.  We would expect 1/20 of the patrons to be both male and from out of town. 
 
 Answer by scott8148(6628)      (Show Source): 
You can  put this solution on YOUR website! the key here may be "expect"
 
 
you know that 1/4 are male and 1/5 are from out of town
 
 
you would expect that the male patrons would have the same portion of out-of-towners as the female patrons
 
 
similarly, you would expect that the out-of-towners would have the same portion of males as the local patrons
 
 
either way you look at it, 1/5 of the males or 1/4 of the out-of-towners will give you the same "expected" result 
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