Listed below are the amounts of weight change (in pounds) for 12 women during their first year of work after graduating from college. Positive values correspond to women who gained weight and negative values
Correspond to women who lost weight. What is the mean weight change? $$\begin{array} { l l l l l l l l l l l l }
3 & - 8 & 3 & - 9 & 11 & - 9 & 14 & 0 & 13 & - 5 & 14 & 7
\end{array}$$
A) 3 lb
B) 8 lb
C) 2.8 lb
D) 3.1 lb

Question

Listed below are the amounts of weight change (in pounds) for 12 women during their first year of work after graduating from college. Positive values correspond to women who gained weight and negative values
Correspond to women who lost weight. What is the mean weight change? $$\begin{array} { l l l l l l l l l l l l } 
3 & - 8 & 3 & - 9 & 11 & - 9 & 14 & 0 & 13 & - 5 & 14 & 7
\end{array}$$
A) 3 lb
B) 8 lb
C) 2.8 lb
D) 3.1 lb

Quizplus · Accepted Answer

To find the mean, we add up all the weight changes and divide by the total number of women:

$ 	ext{Mean weight change} = \frac{3 - 8 + 3 - 9 + 11 - 9 + 14 + 0 + 13 - 5 + 14 + 7}{12} = \frac{32}{12} = 2.67 $

Rounding to the nearest tenth, we get the mean weight change is approximately 2.8 lb. Therefore, the best choice is C.

Listed Below Are the Amounts of Weight Change (In Pounds) 3−83−911−914013−5147\begin{array} { l l l l l l l l l l l l } 3 & - 8 & 3 & - 9 & 11 & - 9 & 14 & 0 & 13 & - 5 & 14 & 7\end{array}3​−8​3​−9​11​−9​14​0​13​−5​14​7​

Listed Below Are the Amounts of Weight Change (In Pounds) $\begin{array} { l l l l l l l l l l l l } 3 & - 8 & 3 & - 9 & 11 & - 9 & 14 & 0 & 13 & - 5 & 14 & 7\end{array}$