document.write( "Question 305833: The Gibbs Baby Food Company wishes to compare the weight gain of infants using their brand versus their competitor’s brand. A sample of 40 babies using the Gibbs products revealed a mean weight gain of 7.6 pounds in the first 3 months after birth. The standard deviation of this sample is 2.3 pounds. A sample of 55 babies using the competitors brand revealed a mean increase of 8.8 pounds with a standard deviation of 2.9 pounds. At 95% level of confidence, can we conclude that the babies using the Gibbs product gained LESS weight? Z-test for Unpaired data \n" ); document.write( "
Algebra.Com's Answer #218958 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! The Gibbs Baby Food Company wishes to compare the weight gain of infants using their brand versus their competitor’s brand. A sample of 40 babies using the Gibbs products revealed a mean weight gain of 7.6 pounds in the first 3 months after birth. The standard deviation of this sample is 2.3 pounds. A sample of 55 babies using the competitors brand revealed a mean increase of 8.8 pounds with a standard deviation of 2.9 pounds. At 95% level of confidence, can we conclude that the babies using the Gibbs product gained LESS weight? Z-test for Unpaired data \n" ); document.write( "-------------------------------------- \n" ); document.write( "I used a 2-Sample Z Test and got the following interval: \n" ); document.write( "--- \n" ); document.write( "-2.247 < u < -0.1534 \n" ); document.write( "------ \n" ); document.write( "Since the interval does not contain zero, we can conclude \n" ); document.write( "the Gibbs group gained Less weight. \n" ); document.write( "======================================= \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( "======================================= \n" ); document.write( " |