Answer:
A. Β d = 0.75.
Step-by-step explanation:
The z-score =( x - m) / d Β where m = the mean and d = the standard deviation.
So we have
(3 - m) / d = 1
3 Β - Β m = Β d.............(1)
and
(3.75 - m) / d = 2
3.75 - m = 2d....... (2)
Subtract (2) - (1):
0.75 = d.
Answer: A 0.75
Step-by-step explanation:
Formula for z-score :
[tex]z=\dfrac{x-\mu}{\sigma}[/tex]
, where x= random variable
[tex]\mu[/tex] = Population mean
[tex]\sigma[/tex] = Standard deviation
As per given , we have
[tex]+1=\dfrac{3-\mu}{\sigma}\\\\\Rightarrow\ \sigma=3-\mu\\\\\Rightarrow\ \mu=3-\sigma---(i)[/tex]
[tex]+2=\dfrac{3.75-\mu}{\sigma}\\\\\Rightarrow\ \mu=3.75-2\sigma---(ii)[/tex]
From (i) and (ii) , we have
[tex]3-\sigma=3.75-2\sigma\\\\\Rightarrow\ 2\sigma-\sigma=3.75-3\\\\\Rightarrow\ \sigma=0.75[/tex]
Hence, the standard deviation of the length of candy bars produced at Carl's Candies is 0.75.
Thus , the correct answer is A. Β 0.75.
