document.write( "Question 727226: Use the following to answer questions 74-75: \n" );
document.write( "A researcher wanted to determine if using an octane booster would increase gasoline mileage. A random sample of seven cars was selected; the cars were driven for two weeks without the booster and two weeks with the booster. Use the definitions of X1 and X2 as given in the table. Consequently, D = X1–X2. \r \n" );
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document.write( "Gasoline Mileage \n" );
document.write( "Without booster, X1 \n" );
document.write( "(mpg) Gasoline Mileage \n" );
document.write( "With booster, X2 \n" );
document.write( "(mpg) \n" );
document.write( "21.2 23.8 \n" );
document.write( "25.4 25.6 \n" );
document.write( "20.9 22.4 \n" );
document.write( "27.6 28.3 \n" );
document.write( "22.8 24.5 \n" );
document.write( "27.3 28.8 \n" );
document.write( "23.4 25.2 \r \n" );
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document.write( "___ 74. What critical value should be used at α = 0.05? \n" );
document.write( " A) –2.447 B) –2.365 C) –1.943 D) –1.895 \r \n" );
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document.write( "___ 75. Determine the mean of the differences. \n" );
document.write( " A) –1.67 B) 6.3 C) 1.67 D) –1.43 \n" );
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