Answer:
The right solution is "5.92". A further solution is provided below.
Explanation:
The given values are:
Total number of customer,
n = 140
The probability of 30% discount,
= [tex]\frac{1}{2}[/tex]
Somewhat by binomial distribution we could perhaps calculate the mean as well as the mean of the standard deviation will be:
= [tex]140\times \frac{1}{2}[/tex]
= [tex]70[/tex]
Now,
The standard deviation will be:
= [tex]\sqrt{np(1-p)}[/tex]
On substituting the given values, we get
= [tex]\sqrt{140\times \frac{1}{2}(1-\frac{1}{2} ) }[/tex]
= [tex]\sqrt{70(1-\frac{1}{2} )}[/tex]
= [tex]\sqrt{35}[/tex]
= [tex]5.92[/tex]