[計量] 幾題印度機經請教
7. Given an Isosceles triangle with two angles denoted as 't' and 'n'. If the
arithmetic mean of two angles of the triangle is 65, then what is the value
of 'n'?
A. 60
B. 65
C. 70
D. 75
E. 80
t+n=130 所以角度有可能是 (50 50 80) (65 65 50) n不就有可能是 65 or 80嗎?
還是說題目內容有說t不等於n，然後我沒發現囧a 韓網的答案是 E
9. A train can complete a trip of 'd' miles in 'h' hours. Find the average
speed in miles/hrs, if on the next day the train completes the trip 30 min
faster than the previous day?
首先不是很確定這題的average speed是單指next day還是next day加previous day?
我自己是假設單指next day，
這題的想法是先把距離設x，利用時間相等的概念去算
所以前一天所花的時間是 x/(d/h) 而隔天則是少花30min 將速度設為a
因此 第一天的時間 第二天的時間
x/(d/h) = x/a-1/2 可得 a = 2d/(2h-d)
但跟韓國人的解答似乎不大相同....
所以想拿上來跟大家討論一下^^ 謝謝!
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