Answer:
Answer: 78 and 82.
Explanation:
We have been given that the average test score of the class was an 80 and the standard deviation was 2. We are asked to find two values between which 68% of class will score.
We know that in a normal distribution approximately 68% of the data falls within one standard deviation of the mean.
So 68% scores will lie within one standard deviation below and above mean that is
Upon substituting our given values, we will get
Therefore, about 68% of the class would score between 78 and 81 and option B is the correct choice.
Step-by-step explanation: Hope this helps :D