There are 10,000 students at the University of Tennessee at Chattanooga. The ave
ID: 3317529 • Letter: T
Question
There are 10,000 students at the University of Tennessee at Chattanooga. The average age of all the students is 24 years with a standard deviation of 9 years. A random sample of 60 students is selected. 1. a. Determine the standard error of the mean. al D b. What is the probability that the sample mean will be larger than 19.5 c. What is the probability that the sample mean will be between 25.5 and 27 years? In a local university, 20% of the students live in the dormitories. A random sample of 150 students is selected for a particular study What is the probability that the sample proportion (the proportion living in the dormitories) is between 0.172 and 0.178? a. What is the probability that the sample proportion (the proportion living in the dormitories) is greater than 0.025? b.Explanation / Answer
Mean is 24 and s is 9
a) for sample size of 60, the standard error is s/sqrt(N)=9/sqrt(60)=1.1619
b) P(xbar<19.5)=P(z<(19.5-24)/1.1619)=P(z<-3.87) or 1-P(z<3.87) , from normal distribution table it is near 0
c) P(25.5<x<27)=P((25.5-24)/1.1619<z<(27-24)/1.1619)=P(1.29<z<2.58) or P(z<2.58)-P(z<1.29)
from normal distribution table we get 0.9951-0.9015=0.0936
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.