Statistics And Probability Question 394
Question: Consider the frequency distribution of the given numbers.
Value | 1 | 2 | 3 | 4 |
---|---|---|---|---|
Frequency | 5 | 4 | 6 | f |
If the mean is known to be 3, then the value of f is
Options:
A) 3
B) 7
C) 10
D) 14
Show Answer
Answer:
Correct Answer: D
Solution:
[d] Mean $ =\frac{1\times 5+2\times 4+3\times 6+4\times f}{5+4+6+f} $ $ i.e.,3=\frac{5+8+18+4f}{15+f}\Rightarrow 45+3f=31+4f $
$ \Rightarrow 45-31=f\Rightarrow f=14. $