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Question 1157998: Every year, the students at a school are given a musical aptitude test that rates them from 0 (no musical aptitude) to 5 (high musical aptitude). This year's results are:
Aptitude Score 0 1 2 3 4 5
Frequency 0 4 1 5 1 3
Round the mean to the nearest hundredth.
The mean (average) aptitude score is
The median aptitude score is
Thank you in advance.
SYL
Answer by KMST(5381)   (Show Source):
You can put this solution on YOUR website! 
I see that students got a score of  ,
 students got a score of  ,
 student got a score of  ,
 students got a score of  ,
student got a score of  ,
and  students got a score of  .
That means the number of students was
The mean is the average of all those  .
To calculate it I have to add those 14 scores.
I could add
 .
However, instead of add a score several times, I could just multiply times its frequency, and add the products:
Oh! And because centuries ago people doing math all over the world decided to agree that multiplications have priority over addition, I can skip all those parentheses, and write
     
Then, 
Round the mean to the nearest hundredth, it says,
so it rounds to 2 and 86/100, because the thousands digit is 7, so we have to round up.
The mean (average) aptitude score is 
The median of a set of values is the one in the middle when we put the values in order.
And if there is an even number of value, we average the two in the middle.
The 14 scores in order are
 .
The seventh and eighth values. both , are the two in the middle, and their average is, of course, .
The median aptitude score is  .
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