Answered: For a certain standardized placement…

Advanced Engineering Mathematics

10th Edition

ISBN:9780470458365

Author:Erwin Kreyszig

Publisher:Erwin Kreyszig

Chapter2: Second-order Linear Odes

Section: Chapter Questions

Problem 1RQ

See similar textbooks

Related questions

Question

For a certain standardized placement test, it was found that the scores were normally distributed, with a mean of 160 and a standard deviation of 20. Suppose that this test is given to 1000 students. (Recall that 34% of z-scores lie between 0 and 1, 13.5% lie between 1 and 2, and 2.5% are greater than 2.)

(a) How many are expected to make scores between 140 and 180?
students

(b) How many are expected to score above 200?
students

(c) What is the expected range of all the scores?

Features Features Normal distribution is characterized by two parameters, mean (µ) and standard deviation (σ). When graphed, the mean represents the center of the bell curve and the graph is perfectly symmetric about the center. The mean, median, and mode are all equal for a normal distribution. The standard deviation measures the data's spread from the center. The higher the standard deviation, the more the data is spread out and the flatter the bell curve looks. Variance is another commonly used measure of the spread of the distribution and is equal to the square of the standard deviation.

Expert Solution