#### Answer

9.84 years, seems to be good.

#### Work Step by Step

By using the values from the picture and the given formula:
$s=\sqrt {\frac{n\cdot[\sum(f\cdot x^2)]-[\sum (f\cdot x)^2]}{n\cdot(n-1)}}=\sqrt {\frac{33\cdot 10552-496^2}{33\cdot 32}}=9.84 \ years.$ This value is lower than 2 and more than 2 other data from other exercises, so seems to be good.