Question

In: Statistics and Probability

Let the mean test score be 80 and standard deviation be 10. Find probability that you...

Let the mean test score be 80 and standard deviation be 10.

  1. Find probability that you will get a score higher than 90.
  2. Find the probability that you will receive a score between 75 and 90.
  3. Find the probability that you will receive a score less than 60

Please explain more, thanks!

Solutions

Expert Solution

For the above example we have given mean test score and the standard deviation.

X represent the mean test score. There is no restrictions on X. X can take any value between -infinity to +infinite.

From the above information it is clear that the we can solve this problem using Normal distribution.

1)

2)

3)

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