ATAR Notes: Forum

VCE Stuff => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Mathematics => Topic started by: ecyrb on August 04, 2010, 09:02:30 pm

Title: Another Hard Westpac Question Help Please!
Post by: ecyrb on August 04, 2010, 09:02:30 pm
The country of Big Wally has a railway which runs in a loop 1080 km long. Three companies - A, B and C run trains on the track and plan to build stations. Company A will build three stations equally spaced at 360km intervals. Company B will build four stations at 270km intervals and Company C will build give stations at 216 km.

The government tells them to space their stations so that the longest distance between consecutive stations is as small as possible. What is this distance in kilometers?


I hardly understand the question let alone know how to solve it.
Again any help is appreciated  :)
Title: Re: Another Hard Westpac Question Help Please!
Post by: pooshwaltzer on August 04, 2010, 09:22:25 pm
12*18 = 216km
Title: Re: Another Hard Westpac Question Help Please!
Post by: ecyrb on August 04, 2010, 10:01:35 pm
Could you please explain how you did that?
Title: Re: Another Hard Westpac Question Help Please!
Post by: pooshwaltzer on August 04, 2010, 10:18:24 pm
A: 3 stations 360km apart
B: 4 stations 270km apart
C: 5 stations 216km apart

LCM = 60 ... 1080/60 = 18

A: 360/18 = 20 ... 20 / 40 / 60
B: 270/18 = 15 ... 15 / 30 / 45 / 60
C: 216/15 = 12 ... 12 / 24 / 36 / 48 / 60

Largest dist is btn 4th station of C and terminal station for A/B/C.
This is (60-48)*18=216km

Title: Re: Another Hard Westpac Question Help Please!
Post by: _avO on August 04, 2010, 10:19:39 pm
Was that last years paper? Because I remember doing that question and I QQed