Car selling explained

[Sal_89]

Hi to all. I spent the last days to figure out how the selling cars thing works in Gran Turismo 4. All is wrote here:


As soon as possible you buy any new car (I still need to test used cars), it will lose 15% of its value together the usual 3/4 of the value. In the case of the AC Cars 427 S/C '66 will be:
- 423200*15÷100=63480. This is the 15% value loss
- 423200-63480=359720. Car's price without that 15%
- 359720÷4=89929. Base sell value

There are 10 selling values basing on mileage. I will explain the process always with the AC Cars 427 S/C '66. The selling values are as follow:
- 0km -> 999.999km New car value
- 1000km -> 2999.999km Price reduction 1
- 3000km -> 4999.999km Price reduction 2
- 5000km -> 9999.999km Price reduction 3
- 10000km -> 14999.999km Price reduction 4
- 15000km -> 24999.999km Price reduction 5
- 25000km -> 39999.999km Price reduction 6
- 40000km -> 59999.999km Price reduction 7
- 60000km -> 99999.999km Price reduction 8
- 100000km+ Price reduction 9

Then the selling values are:
- 89929 Cr.
- 84639 Cr.
- 82523 Cr.
- 81465 Cr.
- 80407 Cr.
- 79350 Cr.
- 68769 Cr.
- 52900 Cr.
- 37029 Cr.
- 10579 Cr.

Lastly, you can calculate the "new car value" of a car just reverting the calculation. Be careful. Also if you revert (multiplying by 4 and add an another 15%) the operation, some loss still occurs. In this case will be 413678 Cr.

 

[Dave A]

Lastly, you can calculate the "new car value" of a car just reverting the calculation. Be careful. Also if you revert (multiplying by 4 and add an another 15%) the operation, some loss still occurs. In this case will be 413678 Cr.

That's because you don't add 15% to reverse the calculation, 15% of the initial price isn't 15% of the price once the 15% has been removed (if that makes sense). I.e. 15% of 423,200 is not the same as 15% of 359,720.

After you multiply by 4, you need to either divide by 85 (100 - 15% = 85) then multiply by 100 or you can multiply by 100 and divide by 85.

So the correct calcualtion is 89,930 x 4 = 359,720
359,720 / 85 = 4,232
4,232 x 100 = 423,200

Hope that makes sense.

Other than that your post is very informative 👍.

 

[Sal_89]

That's because you don't add 15% to reverse the calculation, 15% of the initial price isn't 15% of the price once the 15% has been removed (if that makes sense). I.e. 15% of 423,200 is not the same as 15% of 359,720.

After you multiply by 4, you need to either divide by 85 (100 - 15% = 85) then multiply by 100 or you can multiply by 100 and divide by 85.

So the correct calcualtion is 89,930 x 4 = 359,720
359,720 / 85 = 4,232
4,232 x 100 = 423,200

Hope that makes sense.

Other than that your post is very informative 👍.

Thanks very much for the information
Indeed I never understand why some loss still occours reverting the operation.
You're correct, of course 15% of 423,200 is different than 15% of 359,720. Didn't realized. Thanks again