- CFA Exams
- CFA Level I Exam
- Topic 1. Quantitative Methods
- Learning Module 1. Rates and Returns
- Subject 2. Rates of Return
CFA Practice Question
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?
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.
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.
Correct Answer: B
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 |