Originally posted by VelvetEars
My explanation of how I got to my answers.
[hidden] I judged splitting the fixed cost 4 ways wasn\'t fair as some travelled further than others, mine is based on the relative cost each one incurred. [/hidden]
[hidden] E.g. The cost while A is on the boat is $13, summing the cost for everyone like this I got 77. Hence I had A pay 13/77 of the total cost. [/hidden]
A causes more than 13/77 though.
From 0,0 to 0,3 is three miles to 4,0 is five more miles. A causes an extra mile to get to B's house.
If you cut out A that is four dollars less that needs to be paid.
After cutting out A then B doesn't cause any mileage because they have to pass by B's house to get to C's house.
C causes 2 more dollars because if C were cut out it would only be 5 miles from B to D.
This is harder than you guys make it seem. I think you have to start at the end and work backwards. Eg the cost to go straight to 7,4 is 8.06, the cost to go straight to 7,0 is 7, the cost to go straight to 4,0 is 4 and the cost to go straight to 0,3 is 3; then work forwards and find how much more each added. Eg A added 1 B added 0 C added 2.
This would be A = 4 B= 4 C=9 D=8
I like this answer (though the method can be perfected) as nobody has to use any change. 🙂
Edit: using a different and probably more accepted method I get
a = the cost of A if he were alone
b= the cost of B if he were alone
c= the cost of C if he were alone
d= the cost of D if he were alone
a = 13
b = 14
c = 17
d = 18
I rounded to the nearest dollar.
a+b+c+d = 62
[a/(a+b+c+d)]*25 = A
[b/(a+b+c+d)]*25 = B
[c/(a+b+c+d)]*25 = C
[d/(a+b+c+d)]*25 = D
I rounded to the nearest hundredth.