To find the mean, use the formula:

\(\bar{x} = \frac{\sum x}{n}\)

\(\bar{x} = \frac{48.3 + 55.2 + 59.9 + 67.7 + 60.5 + 75.6 + 62.5 + 57.4 + 53.4 + 49.2 + 64.1}{11} = 59.4\)

To find the standard deviation, use the formula:

\(\sigma = \sqrt{\frac{\sum (x - \bar{x})^2}{n}}\)

Calculate each squared deviation:

\((48.3 - 59.4)^2, (55.2 - 59.4)^2, (59.9 - 59.4)^2, \ldots, (64.1 - 59.4)^2\)

Sum these squared deviations:

\(\sum (x - \bar{x})^2 = 646.64\)

Then, \(\sigma = \sqrt{\frac{646.64}{11}} = 7.68\)