92 - (31 +19) +58
73 + (61 -45) - 26
(63 +17) - (100-24)
(81 -- 35) + (48 - 19)​

92 - (31 + 19) + 58 = 100

1) 31 + 19 = 50

2) 92 - 50 = 42

3) 42 + 58 = 100

73 + (61 - 45) - 26 = 63

1) 61 - 45 = 16

2) 73 + 16 = 89

3) 89 - 26 = 63

(63 + 17) - (100 - 24) = 4

1) 63 + 17 = 80

2) 100 - 24 = 76

3) 80 - 76 = 4

(81 - 35) + (48 - 19) = 75

1) 81 - 35 = 46

2) 48 - 19 = 29

3) 46 + 29 = 75