To start, find the difference between the mean score and the given score.
0.15 %
Practice makes perfect
We have been told that the scores on a test are normally distributed with a mean of 74 and a standard deviation of 8. We will find the probability that a randomly chosen junior has a score above 98.
x≥ 98
First, let's find the difference between 98 and the mean.
98- 74= 24
Then, we will divide the difference by the standard deviation.
24/8=3
Thus, 98 is 3 standard deviations above the mean. To find the probability, we will shade the percentage of data which is no less than 3 standard deviations above the mean.
Finally, we can see that the probability of choosing a junior with a score above 98 is 0.15 %.
