Answer
Interaction P-value $=0.880$. Do not reject the null hypothesis.
There is not enough evidence to conclude that there is an interaction between Age and Diet.
Work Step by Step
$H_0:$ there is no interaction between Age and Diet.
versus
$H_1:$ there is an interaction between Age and Diet.
In MINITAB 18, enter the data according to the table below.
Select Stat -> ANOVA -> General Linear Model -> Fit General Linear Model
In Responses enter Birth Weight (g). In Factors enter Age Diet (C1 C2).
Click Model. In Factors and covariates highlight both Age and Diet. Click Add (to the right of Interactions through order). Age*Diet will appear in 'Terms in the model'. Click OK.
Click Ok.
The interaction P-value $=0.880$
