OG PS-Q155

[wisson0927]

155.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 stroke. 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?
(A) 72
(B) 50
(C) 48
(D) 46
(E) 44

ans:D

麻煩囉~~~~

[liwuu]

155.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 stroke. 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?
(A) 72
(B) 50
(C) 48
(D) 46
(E) 44

ans:D

麻煩囉~~~~

由這句話At 6:00 the time lapse between the beginning of the first stroke and the end of the last stroke is 22 seconds.可以知道每個間距含鍾聲的時間為22/(6+5)=22/11=2 seconds (6鐘聲+5間距)
所以12:00時,共2*23=46(12鐘聲+11間距)

[wisson0927]

嗯~~~不好意思，請問一下
6鐘聲和5間距
是怎麼得來的呢？
謝謝!!!

[myron]

嗯~~~不好意思，請問一下
6鐘聲和5間距
是怎麼得來的呢？
謝謝!!!

因為題目說每鐘點敲一下,6:00所以敲六下,
在敲第一下與第二下之間有一間距,敲六下所以有五間距.

[chris8888]

1. 就是說假設六點時, 題目說他會敲6下, 每一個stroke(敲) equals to interval
敲六下那表示中間的intervals會有5個.
噹 ~ 噹 ~ 噹 ~ 噹 ~ 噹 ~ 噹 <== 不是嗎? 每一個噹都要花掉時間, ~ <== 這個符號就是interval, 也要花時間, 兩者時間相等
經過計算, 六點時候有六的噹, 五個~ ==> 合計11個, 每個的duration都是一樣的, 因此 22秒 / 11 = 2秒 / 每個噹 or 每個~

12點表示有
噹 ~ 噹 ~ 噹 ~ 噹 ~ 噹 ~ 噹 ~ 噹 ~ 噹 ~ 噹 ~ 噹 ~ 噹 ~ 噹 <== 12個噹, 11個~
一共是23個duration * 2秒 = 46秒.
D對