IN A SAMPLE OF 51 GAME SHOW CONTESTANTS, THE MEAN WINNINGS AMOUNT IS $9,820 WITH A STANDARD DEVIATION OF $1,750. c. With .10 significance, test the claim that the standard deviation in winnings amount is $1800. Use CRITICAL VALUE METHOD. Solution Let o be the population standard devation Ho: o=1800 Ha: o not equal to 1800 The test statistic is Chisquare= (n-1)*s^2/o^2 =50*1750^2/1800^2 =47.26 Given a=0.1, the critical values are chisquare with 0.05, df=n-1=50 is 34.76 (from chisquare table) chisquare with 0.95, df=50 is 67.5 Since 47.26 is between 34.76 and 67.5, we do not reject Ho. So we can conclude that the standard deviation in winnings amount is $1800.