Statistics And Probability Question 460
Question: If the mean of the distribution is 2.6, then the value of y is
| Variate x | 1 | 2 | 3 | 4 | 5 |
|---|---|---|---|---|---|
| Frequency f of x | 4 | 5 | Y | 1 | 2 |
Options:
A) 24
B) 13
C) 8
D) 3
Show Answer
Answer:
Correct Answer: C
Solution:
[c] Mean $ =\frac{\sum\limits_{i=1}^{n}{f_{i}x_{i}}}{\sum\limits_{i=1}^{n}{f_{i}}} $
$ \therefore 2.6=\frac{1\times 4+2\times 5+\times 3\times y+4\times 1+5\times 2}{4+5+y+1+2} $
$ \Rightarrow 31.2+2.6y=28+3y\Rightarrow 0.4y=3.2\Rightarrow y=8 $
BETA
