Solved on Sep 20, 2023
Find the area under the normal curve to the right of an IQ score of , given a mean of and a standard deviation of . Round the answer to four decimal places.
STEP 1
Assumptions1. The IQ scores are normally distributed.
. The mean of the IQ scores is100.
3. The standard deviation of the IQ scores is15.
4. We are looking for the area under the curve to the right of the score86.
STEP 2
First, we need to standardize the score86 to a z-score. The z-score is a measure of how many standard deviations an element is from the mean. We can calculate it using the formulawhere- X is the score we are interested in, - μ is the mean, and- σ is the standard deviation.
STEP 3
Now, plug in the given values for X, μ, and σ to calculate the z-score.
STEP 4
Calculate the z-score.
STEP 5
Now that we have the z-score, we need to find the area to the right of this z-score. Since the total area under the curve is1, the area to the right of the z-score is1 - the area to the left of the z-score. We can find the area to the left of the z-score using the standard normal distribution table or a calculator that can calculate normal probabilities.
STEP 6
Using the standard normal distribution table or a calculator, we find that the area to the left of z = -0.9333 is approximately0.1753.
STEP 7
Now, plug in the value for the area to the left into the formula to find the area to the right.
STEP 8
Calculate the area to the right.
The area of the shaded region, to four decimal places, is0.8247.
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