s. IQ Scores are normally distributed in the population. Who has higher 1Q: a st

Question

s. IQ Scores are normally distributed in the population. Who has higher 1Q: a student with a 120 1Q on a scale where 100 is the mean and 10 is the standard deviation, or a professor with a 128 1Q on a scale where 100 is the mean and 15 is the standard deviation? Briefly explain your answer. Use the z-cores and the corresponding percentiles shown at the top of the next column to solve this exercise. Test scores are normally distributed with a mean of 74 and a standard deviation of 10. What percentage of the scores are above 88 9. z-scores Percentile 1.1 1.2 1.3 1.4 1.5 86.43 88.49 90.32 91.92 93.32 10. Using a random sample of 100 students from a campus of approximately 12000 students, 60% of the students in the sample said they were very satisfied with their professors. Find the margin of error in this percent. * 100%

Explanation / Answer

Question 8

Here whichever value has more Z value than the other will have more IQ level.

So for the given student

Z = (120 - 100)/10 = 2

for the professor

Z = (128 - 100)/15 = 28/15 < 2

so the student has better IQ than the professor

Q.9

Here X = 88

Mena = 74

and Standard deviation = 10

Z = (88 - 74)/10 = 1.4

so The Pr(X > 88) = 1 - Pr(Z < 1.4) = 1 - 91.92/100 = 1 - 0.9192 = 0.0808

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.