新GRE考试数学学习策略:standard variation

2026-05-15
standard variation
  一组数中,每个数与平均数之差的平方和,再除以这组数的个数n

  例: standard variation of 0,2,5,7,6 is: _ 2 2 2 2 2_

  |_(0-4) +(2-4)+(5-4)+(7-4)+(6-4)_|/5=6.8