-15,78+34,45-24,86+4,12-81,74
-15,78-(-34,45)-24,86-(-4,12)+(-81,74) =
- 15, 78 + 34, 45 - 24, 86 + 4, 12 - 81, 74 = - 83,81
-15,78+34,45-24,86+4,12-81,74
-15,78-(-34,45)-24,86-(-4,12)+(-81,74) =
- 15, 78 + 34, 45 - 24, 86 + 4, 12 - 81, 74 = - 83,81