问一道题。

DUCKDUCKGO

有一道题我老是错，请问有什么方法吗

Five friends received their scores on a quiz. What was the standard deviation of the 5 scores?

(1) The scores were all equal to each other.

(2) The range of the scores was equal to 0.

答案是EACH statement ALONE is sufficient.

TracyZhh123

第一个是每个相等，波动等于0  所以standard deviation=0  第二个是最大-最小=0 等同于第一个条件，大家都想等，sd=0

DUCKDUCKGO

TracyZhh123 发表于 2019-5-8 13:23
第一个是每个相等，波动等于0  所以standard deviation=0  第二个是最大-最小=0 等同于第一个条件，大家都 ...

谢谢