I have a spreadsheet that needs to lookup a value but it is dependent on two
values.

Master Sheet reads
A B C
74% 5 (need lookup value)
83% 4 (need lookup value)
The C column needs to be the lookup value for both A & B

My Lookup values
A B C
1 0% 74% (The range for C is 60%-150%)
2 2.5% 74% (The range for C is 60% -150%)
3 3.5% 74% (The range for C is 60% -150%)
4 5.0% 74% (The range for C is 60% -150%)
5 7.0% 74% (The range for C is 60% -150%)

Please help