Determining a number given two sets of range

Question

I'm trying to assign a value (in the range $A$) given a score (in the range $B$). For example, the lowest score that you can get is $60$, and the highest score is $100$. If you get $60$, you are rewarded with $10000$ points, the minimum number of points you can ever get. If you get $100$, you are rewarded with $20000$ points, the maximum. So, given some score $X$, how can you determine the points rewarded proportionately?

Answer 1

With that little information, a simple linear interpolation would reward a score of $x$ with $$ 10000+(20000-10000)\cdot\frac{x-60}{100-60}=250x-5000$$ points.