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In: Statistics and Probability

. Suppose the scores on a chemistry test were normally distributed with a mean of 78...

. Suppose the scores on a chemistry test were normally distributed with a mean of 78 and a standard deviation of 10. If a student who completed the test is chosen at random,

  1. Find the probability that the student earned fewer than 75 points.
  2. Find the probability that the student earned at least 70 points.
  3. Find the probability that the student earned between 80 and 90 points.
  4. Find the probability that the student earned either less than 80 points or more than 90 points.

For a I know you do 75-78/10=-.8 but I dont know how someone goes from P(x<75)=0.382 How do get the .382? Please show work I'd much appreciate it

12E.The body temperatures of adults are normally distributed with a mean of 98.60 and a standard deviation of 0.73. What temperature represents the 85th percentile

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orchestra answered 2 years ago
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