Assigning values to a variable set

[John A]

I am trying to create a spreadsheet that allows me to assign a predetermined
number to a specific set of numbers.
(This is to help me with automation of grading students.)

There is a predetermined grid we must follow that has an x axis zero to 10
The y axis is zero to 50.
The rest of the grid tells the proper grade that a student would get is they
score specific numbers. For example a 50 and a 10 would be a 100%, a 45 and
a 7 would be another number like a 83%

I want to be able to enter the 2 (X and Y grid) numbers for students and
have excel calculate the proper percentage score using the grid information
that I would also enter.

So if a student received a 37 and an 6 or any other set of two numbers-
excel would automatically enter the final grade in a separate cell.

Is this an IF statement? What is the easiest way to approach this?

Thank you!

 

[JLatham]

Assume your grid is on a sheet named Grid and starts at A1 (actually A1 is
empty), with 0,1,2,3 ... 8, 9, 10 in B1 through L1, and 0, 1, 2 ... 48, 49,
50 in A2:A52.

General formula
=INDEX(Grid!$A$1:$L$52,MATCH(yValue,Grid!$A$1:$A$52),MATCH(xValue,Grid!$A$1:$L$1))

Assume you enter y coordinate in cell A1 of another sheet, and x coordinate
in B1 and then in C2 (or elsewhere) you could have formula:
=INDEX(Grid!$A$1:$L$52,MATCH(A1,Grid!$A$1:$A$52),MATCH(B1,Grid!$A$1:$L$1))