The mean of a group of numbers is the division of the sum of each individual value by the number of samples. With this in mind, we have:
[tex]\mu=\frac{34.2+43.6+29.88+40.1+39.4}{5}[/tex][tex]\mu=\frac{187.18}{5}=37.436[/tex]The mean weight of the samples is 37.436 kg.