For a statistical data \( x_1, x_2, \ldots, x_{10} \) of \( 10 \) values, a student obtained the mean as \( 5.5 \) and \( \sum_{i=1}^{10} x_i^2 = 371 \). He later found that he had noted two values in the data incorrectly as \( 4 \) and \( 5 \), instead of the correct values \( 6 \) and \( 8 \), respectively. The variance of the corrected data is:
