The highway fuel economy of a 2016 Lexus RX 350 FWD 6-cylinder 3.5-L automatic 5-speed using premium fuel is a normally distributed random variable with a mean of μ = 24.50 mpg and a standard deviation of σ = 3.50 mpg.
(a) What is the standard error of X¯¯¯
, the mean from a random sample of 9 fill-ups by one driver?
(Round your answer to 4 decimal places.)
(b) Within what interval would you expect the
sample mean to fall, with 95 percent probability? (Round
your answers to 4 decimal places.)
Get Answers For Free
Most questions answered within 1 hours.