Mean = $65.85
S.D. = $36
For 1 s.d.: 65.85 - 36 ≤ x ≤65.85 + 36 => 29.85 ≤ x ≤ 101.85
But $25.60 and $126.40 does not fall within 1 standard deviation.
Therefore, all the prices fall within 2 standard deviations.
Mean = (146 + 189 + 246 + 178 + 203)/5 = 192.4
S.D. = sqrt[(146 - 192.4)^2 + (189 - 192.4)^2 + (246 - 192.4)^2 + (178 - 192.4)^2 + (203 - 192.4)^2] = 73.2
For 1 S.D.: 192.4 - 73.2 ≤ x ≤ 192.4 + 73.2 => 119.2 ≤ x ≤ 265.6
All the weight falls within 1 standard deviation of the mean.
