The Gibbs Baby Food Company wishes to compare the weight gain of infants...

The Gibbs Baby Food Company wishes to compare the weight gain of infants
using their brand versus their competitor's. A sample of 40 babies using
the Gibbs products revealed a mean weight gain of 7.6 pounds in the
first three months after birth. The standard deviation of the sample was
2.3 pounds. A sample of 55 babies using the competitor's brand revealed
a mean increase in weight of 8.1 pounds, with a standard deviation of
2.9 pounds. At the .05 significance level, can we conclude that babies
using the Gibbs brand gained less weight? Compute the p-value and
interpret it.  Set this up using the 5-step hypothesis testing procedure
outlined in your textbook:


1.     State the null & alternative hypotheses - remember that the
alternative hypothesis is our research question



2.     Design the study and select a level of significance (alpha) -
here, it's given to us



3.     Identify the test statistic - which of the formulas will work
best with our data?)



4.     Formulate a decision rule - under what conditions can we reject
the null hypothesis and accept the alternate?



5.     Take a sample and arrive at a decision to reject or not reject
the null - write a short summary statement communicating your decision