Answer
Mean:
$y ̅ =33.1~lb$
Standard deviation:
$y ̃=3.44~lb$
Work Step by Step
$y ̅ =\frac{∑y_i}{n}=\frac{35.1+30.6+36.9+29.8}{4}=\frac{132.4}{4}=33.1$
$s=\sqrt {\frac{∑(y_i-y ̅ )^2}{n-1}}=\sqrt {\frac{(35.1-33.1)^2+(30.6-33.1)^2+(36.9-33.1)^2+(29.8-33.1)^2}{4-1}}=3.44$
