calculation question

[Gordon]

I am notoriously rubbish at simple maths. What is the simplest way to calculate cost per km or cost per mile for a railway fare?

 

[jfollows]

https://timetables.fabdigital.uk/nrt/may2025/000.6 NRT May 2025 Mileages.pdf gives you mileages

 

[The exile]

I am notoriously rubbish at simple maths. What is the simplest way to calculate cost per km or cost per mile for a railway fare?

Take the cost of a journey (probably convert it into pence by multiplying by 100) and divide it by the length of the journey. Thus a 10 mile journey that costs £12.50 (=1250p) costs 1250 pence divided by 10 per mile. Or, in this case 125p (=£1.25)per mile.
In the dim and distant past this was the way fares were set (so many pence per mile) . Many continental railways still work on adaptations of this (getting cheaper per km the further you go or using “tariff kilometres which aren’t necessarily the true distance).