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Basic Question 2 of 12

In a group of 12 scores, the largest score is increased by 36 points. What effect will this have on the mean of the scores?

A. It will be increased by 12 points.
B. It will be increased by 3 points.
C. There is no way of knowing exactly how many points the mean will be increased by.

User Contributed Comments 10

User Comment
rainatt (X+36)/12=X/12+3
rinkoo can anyone make it more clear???
AyshaAli to find the mean we have to find the average, hence 36 should be divided by 12 which is the no. scores
chek let,the first nos are 1+2+3+...+12=78, avg=78/12=6.5, If i change 12th no 12 with more 36 i.e 48 then, 1+2+3+...+11+48= 114,avg is=114/12=9.5,incresed by 3.this is applicable for every number.
Meka76 Great explanation Chek
albert2008 Basically you just divide the score increase by N. In this case N = 12. I'm not a math genius so I had to plug in some other numbers to verify check's explanation.
RCapistrano 36/12 = 3

You can also check by picking any number and multiply that number 12 times --- 2(12) =24

24 + 36(increase)/12 = 5
24 + 36 + 36 = 8

and so on...

and the change will always be 3.
anniepass there are 12 scors, each one has equal weight by 1/12, then 36 * 1/12 = 3
rsanfo x+36/12 = x/12 + 36/12 = x/12 + 3.
No matter what x is, the mean increases by 3.
Konstantis m=x/12 , x=12*m (m: average before the increase, x the total of your scores)

m+y=(x+36)/12 (Y is the increase of average)

replace x with 12*m

you take m+y=m+3

Y=3
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Learning Outcome Statements

calculate and interpret different approaches to return measurement over time and describe their appropriate uses;

CFA® 2024 Level I Curriculum, Volume 1, Module 1.