(34+19)-3-(15+18)+(28+29); (59+27)-(20-9)-30+(23+18)

Первый пример.

(34 + 19) - 3 - (15 + 18) + (28 + 29) = 74;

34 + 19 = 53;

53 - 3 = 50;

15 + 18 = 33;

50 - 33 = 17;

28 + 29 = 57;

17 + 57 = 74.

Второй пример.

(59 + 27) - (20 - 9) - 30 + (23 + 18) = 86;

59 + 27 = 86;

20 - 9 = 11;

86 - 11 = 75;

75 - 30 = 45;

23 + 18 = 41;

45 + 41 = 86.