The fuel economy of a 2011 Lexus RX 350 2WD 6 cylinder 3.5 L automatic 5?speed u
ID: 3432989 • Letter: T
Question
The fuel economy of a 2011 Lexus RX 350 2WD 6 cylinder 3.5 L automatic 5?speed using premium fuel is a normally distributed random variable with a mean of ? = 22 MPG and a standard deviation of ? = 1.25 MPG.
Within what interval would you expect the sample mean to fall, with 98 percent probability? (Round your answers to 4 decimal places.)
The fuel economy of a 2011 Lexus RX 350 2WD 6 cylinder 3.5 L automatic 5?speed using premium fuel is a normally distributed random variable with a mean of ? = 22 MPG and a standard deviation of ? = 1.25 MPG.
The fuel economy of a 2011 Lexus RX 350 2WD 6 cylinder 3.5 L automatic 5?speed using premium fuel is a normally distributed random variable with a mean of ? = 22 MPG and a standard deviation of ? = 1.25 MPG. What is the standard error of X , the mean from a random sample of 25 fill?ups by one driver? (Round your answer to 4 decimal places.) Within what interval would you expect the sample mean to fall, with 98 percent probability? (Round your answers to 4 decimal places.)Explanation / Answer
(a)the standard error =s/vn
=1.25/sqrt(25)
=0.25
-----------------------------------------------------------------------------------------------------------
(b) Given a=1-0.98=0.02, Z(0.01)=2.33 (from standard normal table)
So the lower bound is
xbar - Z*s/vn=22 - 2.33*0.25 = 21.4175
So the upper bound is
xbar + Z*s/vn =22 + 2.33*0.25=22.5825
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.