Scores of an IQ test have a bell-shaped distribution with a mean of 100 and a standard deviation of 20. Use theempirical rule to determine the following(a) What percentage of people has an IQ score between 40 and 160?(b) What percentage of people has an IQ score less than 60 or greater than 140?(c) What percentage of people has an IQ score greater than 120?(a) % (Type an integer or a decimal.)

a)Assume the random variable x defines the score of IQ test.

Answered: Scores of an IQ test have a bell-shaped…

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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Diastolic blood pressure is a measure of the pressure when arteries rest between heartbeats. Suppose diastolic blood pressure levels in women are normally distributed with a mean of 70.8 mm Hg and a standard deviation of 10.8 mm Hg. Complete parts (a) and (b) below. a. A diastolic blood pressure level above 90 mm Hg is considered to be hypertension. What percentage of women have hypertension? % (Round to two decimal places as needed.) b. If we randomly collect samples of women with 16 in each sample, what percentage of those samples have a mean above 90 mm Hg? (Round to two decimal places as needed.)
Claim: The mean pulse rate (in beats per minute) of adult males is equal to 69 bpm. For a random sample of 171 adult males, the mean pulse rate is 68.2 bpm and the standard deviation is 10.91 bpm. Find the value of the test statistic.
Claim: The mean pulse rate (in beats per minute) of adult males is equal to 69 bpm. For a random sample of 136 adult males, the mean pulse rate is 69.6 bpm and the standard deviation is 11.4 bpm. Find the value of the test statistic.
I Professor Brown administered an achievement test, which as he remembers from years of experience, yielded a population mean score of 85. If his class of 25 students obtained a mean score of 89 with standard deviation score of 14, can the professor claim that his class is a superior class? Assume that the mean score is approximately normally distributed. Use a = 0.01
blem #7: Roll two 8-sided fair dice independently. Let X and Y denote the numbers appeared on the upper faces of the first die and the second die respectively. Set W = min (X, Y), V = X+Y. Problem #7(a): Problem #7(b): (a) Find P{W = 1}. (b) P{V ≤ 3}. Round your answer to 4 decimals. Round your answer to 4 decimals.
Claim: The standard deviation of pulse rates of adult males is less than 10 bpm. For a random sample of 140 adult males, the pulse rates have a standard deviation of 9.3 bpm.
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Claim: The standard deviation of pulse rates of adult males is more than 12 bpm. For a random sample of 172 adult males, the pulse rates have a standard deviation of 11.5 bpm. Find the value of the test statistic?
Is the difference between the mean annual salaries of registered nurses in State A and State B equal to $10,500? To decide, you select a random sample of registered nurses from each state. The results of each survey are shown. Assume the population standard deviations are o, = $8337 and o, = $7633. At a = 0.01, what can you conclude? Registered Nurses in State A Registered Nurses in State B 75,695 70,695 %3D %3D X1 X2 n1 30 n2 25 What are the null and alternative hypotheses for this test? A. Ho: H1 - H22 10,500 Ha: H1 - H2 10,500 Ha: H1 - H2s 10,500 O F. Ho: H1 - H2 S 10,500 Hai H1 - H2 > 10,500 Determine the critical value(s). (Round to three decimal places as needed. Use a comma to separate answers as needed.)
I need help in this question of Probabiltiy The 21st Century grade of students in a certain school is normally distributed with a mean of 87.18 and a standard deviation of 2.99. What range of scores represents the middle 75% of the students?a)(85.12,91.25)b)(82.5,90.5)c)(81.53,88.67)d)(83.74,90.62)
Claim: The mean pulse rate (in beats per minute) of adult males is equal to 69 bpm. For a random sample of 171 adult males, the mean pulse rate is 70.3 bpm and the standard deviation is 11.4 bpm. Find the value of the test statistic.
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