## Elementary Statistics (12th Edition)

We calculate the quadratic mean: $\sqrt {\frac{3\cdot 0^{2}+2\cdot100^{2}+2\cdot(-100)^{2}+2\cdot162^{2}+2\cdot(-162)^{2}}{11}}=114.8$. The actual mean is 0, so it is a lot more than the actual mean.