answer the question. 12) focus groups of 12 people are randomly selected to discuss products of the famous…

answer the question. 12) focus groups of 12 people are randomly selected to discuss products of the famous company. it is determined that the mean number (per group) who recognize the famous brand name is 7, and the standard - deviation is 0.60. would it be unusual to randomly select 12 people and find that greater than 10 recognize the famous brand name? a) yes b) no
Answer
Explanation:
Step1: Recall the range - rule - of - thumb for unusual values
Unusual values are outside the range of $\mu\pm2\sigma$ or $\mu\pm3\sigma$. We'll use $\mu\pm2\sigma$ here. Given $\mu = 7$ and $\sigma=0.60$.
Step2: Calculate the lower and upper bounds of the usual range
The lower bound is $\mu - 2\sigma=7 - 2\times0.60=7 - 1.2 = 5.8$. The upper bound is $\mu + 2\sigma=7+2\times0.60=7 + 1.2 = 8.2$.
Step3: Check if 10 is within the usual range
Since $10>8.2$, 10 is an unusual value.
Answer:
A. Yes