Pleases show all work in all questions and a 5 star rating will be given to some
ID: 3288536 • Letter: P
Question
Pleases show all work in all questions and a 5 star rating will be given to some one who can show work and explain their work. thank you.
# (2) there was IQ scores that can be modeled with a normal distribution with a mean of 100 and a standard deviation of 15.
(i) Write a formula for the density function of IQ scores.
(ii) Estimate a part of the population of IQs with 115 and 120. Explain estimate.
(iii) Compute actual value of the estimate.
(iiii)What range of scores that lie across on the other side of the mean represent the same fraction of the population. Please explain this probability in sentences.
Explanation / Answer
IQ scores have a normal distribution with a mean of 100 and a standard deviation of 15. What two IQs separate the middle 90 percent from the remainder of the distribution?-----------------------------
Use your z-chart to find the z-value which has 5% of the population above it.
That would be 1.645
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Find th z-value which has 5% of the population below it.
That would be -1.645
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Find the x-values that correspond to these z-values:
z(x) = (x-u)/s
1.645 = (x-100)/15
x = 124.675
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-1.645 = (x-100)/15