4. Researchers working for a sports drink company would like to know if a newblend if its popular sports drink can help improve marathon runners' final runningtime. Marathon times, Y, are known to follow a Normal distribution. Suppose thatrunners using the old blend sports drink have a mean finishing time of 300 minutes(µ = 300 minutes). A random sample of 20 runners was selected to use the newblend of sports drink in a marathon, finishing with an average time of 270 minutesand a standard deviation of 20 minutes (y = 270 min, s = 20 min). Can it be claimed thatthe new blend lowers finishing times? COr is it possible that random chance alone canexplain the discrepancy? Carry out a hypothesis test of the true mean u using the 4-step procedure. Set your alpha-level to 0.05.%3Dc. Which test statistic and sampling distribution under the null should we use?O i. z-score; standard NormalO ii. t-statistic; Student'st

Given: n= 20.0 ,x̄= 270.0 ,s= 20.0 µ= 300.0 ,significance level(∝)= 0.05 ,degree of freedom= 19.0

Answered: 4. Researchers working for a sports…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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