How can you make three nines 20 using any mathematical symbols?

Answer 1

perhaps you mean without using any other numbers? a lot depends on your constraints 9/9+9=10 which is 20 expressed in base 20 if you allow transformal mapping use Y=Nx20/27. Then each 9 transforms to 20/3 and Y1+Y2+Y3=20 There may be other transforms not involving constants that work. For instance, if we round our result to the nearest 10, ROUND [sqrt(9) x sqrt(9) + 9 ] gives 20. OR for some unspecified power N, we wish 9^n+9^n+9^n=20 using n~ 1.1582 solves the relation