An IQ test has a mean of 100 and a standard deviation of 15. Assume a normal distribution. Find the following probabilities: What is the probability that someone scores more than 95 points? What is the probability that someone scores more than 125 points? What is the probability that someone scores between 110 and 120
Added by Sergio R.
Step 1
The probability that someone scores more than 95 points: First, we need to convert the score of 95 to a z-score. The z-score is calculated by subtracting the mean from the value and then dividing by the standard deviation. So, for 95, the z-score would be Show more…
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Assume that adults have IQ scores that are normally distributed with a mean of 100 and a standard deviation of 15 (as on the Wechsler test). For a randomly selected adult, find the indicated probability or IQ score. Round IQ scores to the nearest whole number. (Hint: Draw a graph in each case.) Find the probability that a randomly selected adult has an IQ between 90 and 110 (referred to as the normal range).
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