87 + 92 = 18; ((8+7)+(9-2)-4) 57 + 83 =13; ((5+7)+(8-3)-4) 12 + 61 = 4; ((1+2)+(6-1)-4) therefore 62 + 31 = ? ((6+2)+(3-1)-4) = 6

If in a coded language 1.67 * 2.31 = 129 2.39 * 4.31 = 202 6.78 * 4.87 = 816 Then 7.16 * 9.13 = ?

If

26+64 = 63, 32+48 = 83, 43+57 = 74

Then what is the value of

68+39 = ?