Here is a classic sudoku puzzle at an intermediate level. After you solve it we will go over the exercises and associate the number of the letter with the answer. Place in the coordinates and find the place of the cache:
A3+C5= A
D2+F8=B
D3+I9=C
F4+H1=D
F6+G7=E
E5+B1=F
N 32° (A-3).A(B-A)F
E 34° (E-1)D.(C-E)00