有道数学题向大家请教: the residents of town X participated in a survey to determine the number of hours per week each resident spent watching TV. The distribution of the results of the survey had a mean of 21 hours and standard deviation of 6 hours. the number of hours that Pat, a resident of Town X, watched television last week was between 1 and 2 standard deviations below the mean. What number of hours Pat Watched last week? 呵呵,这道题看来还是要读题,一到两个注差,看成注差改变了。自己给自己找麻烦。此问题已解。还是要谢谢CD
[此贴子已经被作者于2009-4-9 10:30:27编辑过] |