A certain clock marks every hour by striking a number of times equal to the hour, and the time required for a stroke is exactly equal to the time interval between strokes. At 6:00 the time lapse between the beginning of the first stroke and the end of the last stroke is 22 seconds. At 12:00, how many seconds elapse between the beginning of the first stroke and the end of the last stroke?
72
50
48
46
44
敲钟和间隔时间一样,6点时敲6下隔5次,共11次,22秒,每下2秒
12点时,敲12下,隔11次,共23次,46秒
敲钟和间隔时间一样
敲6次+间隔5次 = 11
22/6 = 2
12+11 = 23
23*2 =46
6点:6下+5间隔=11~22秒
and the time required for a stroke is exactly equal to the time interval between strokes. 敲击所需要的时间等于敲击的时间间隔6-1=5
所以22秒内总共走了(5+6=11),所以每走一步花2秒。
敲钟和间隔时间一样,6点时敲6下隔5次,共11次,22秒,每下2秒
12点时,敲12下,隔11次,共23次,46秒
摆坏了,6点的时候应该摆六下花22秒,问12点的时候摆12下应该花几秒。
所以12点时需要时间=2*(11+12)=46
and the time required for a stroke is exactly equal to the time interval between strokes. 敲击所需要的时间等于敲击的时间间隔6-1=5
所以22秒内总共走了(5+6=11),所以每走一步花2秒。
12点时,敲12下,隔11次,共23次,46秒
所以12点时需要时间=2*(11+12)=46
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是不是理解成敲钟的声音更直接一些?声音和间隔持续时间一样,6点就是6次声音+5个间隔,12点是12次声音+11个间隔。
理解成“持续时间一样”应该可以吧,我一开始认为声音是瞬时 错选48
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