推 vanillatown:答案是B嗎? 11/05 12:54
推 reznor:Mean:100, 1 standard deviation lower=100-22.4=77.6 11/05 15:01
→ reznor:所以兩人 11/05 15:02
推 minimumi:了解了～謝謝! 11/05 16:47
166.
70, 75, 80, 85, 90, 105, 105, 130, 130, 130
The list shown consists of the times, in seconds, that it took each of 10
schoolchildren to run a distance of 400 meters. If the standard deviation
of the 10 running times is 22.4 seconds, rounded to the nearest tenth of a
second, how many of the 10 running times are more than 1 standard deviation
below the mean of the 10 running times?
(A) One
(B) Two
(C) Three
(D) Four
(E) Five
想請問一下這題該怎麼解~
謝謝!
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