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back to boardWhy the answer of example isn't 44? Posted by Tinker 1 Mar 2008 14:18 Re: Why the answer of example isn't 44? The man should be at the floor before he call for the elevator. My English is so poor.... Re: Why the answer of example isn't 44? I still do not understand. In the example case. If Petr go to floor 45: He take 4.8*5 = 24 second to go to floor 45. The elevator take 0.2*48 + 15 + 0.2*44 = 33.4 seconds to go to floor 1, stop there 15 seconds, and then go up to floor 45. So, Petr must wait for 33.4-24 = 9.4 secs, go in for 5 secs, and go down take 44*0.2 = 8.8 secs The total time is 24 + 9.4 + 5 + 8.8 = 47.2 secs Now compare with Pert go to floor 44: He take 4.8*6 = 28.8 second to go to floor 44. The elevator take 0.2*48 + 15 + 0.2*43 = 33.2 seconds to go to floor 1, stop there 15 seconds, and then go up to floor 44. So, Petr must wait for 33.2-28.8 = 4.4 secs, go in for 5 secs, and go down take 43*0.2 = 8.6 secs The total time is 28.8 + 4.4 + 5 + 8.6 = 46.8 secs! So, go to floor 44 is better, isn't it? Edited: uh oh... I misunderstand the question. The elevator will no go up till Petr press the button of elevator. Sorry. Edited by author 07.03.2008 18:57 Re: Why the answer of example isn't 44? I understand too... Edited by author 25.03.2008 23:50 |
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