483 + 257 = 740
$\snippet{name: op_column, sign: '+', x: '483', y: '257', z: '740'}$
 
621 + 199 = 820
$\snippet{name: op_column, sign: '+', x: '621', y: '199', z: '820'}$
 
356 + 207 = 563
$\snippet{name: op_column, sign: '+', x: '356', y: '207', z: '563'}$
 
820 − 164 = 656
$\snippet{name: op_column, sign: '-', x: '820', y: '164', z: '656'}$
 
9 * 9 − 59 = 81 − 59 = 22
 
408 − 262 = 146
$\snippet{name: op_column, sign: '-', x: '408', y: '262', z: '146'}$
 
15 * 8 : 3 = (10 + 5) * 8 : 3 = (10 * 8 + 5 * 8) : 3 = (80 + 40) : 3 = 120 : 3 = 40
 
30 * 8 : 2 = 240 : 2 = (120 + 120) : 2 = 120 : 2 + 120 : 2 = 60 + 60 = 120
 
60 * 6 : 3 = 360 : 3 = (300 + 60) : 3 = 300 : 3 + 60 : 3 = 100 + 20 = 120
 
6 * 16 : 8 − 2 = 6 * (10 + 6) : 8 − 2 = (6 * 10 + 6 * 6) : 8 * 2 = (60 + 36) : 8 − 2 = 96 : 8 − 2 = (80 + 16) : 8 − 2 = (80 : 8 + 16 : 8) − 2 = (10 + 2) − 2 = 12 − 2 = 10
 
6 * 16 : (8 − 2) = 6 * (10 + 6) : 6 = (6 * 10 + 6 * 6) : 6 = (60 + 36) : 6 = 60 : 6 + 36 : 6 = 10 + 6 = 16
 
4 * 15 : 5 * 4 = 4 * (10 + 5) : 5 * 4 = (4 * 10 + 4 * 5) : 5 * 4 = (40 + 20) : 5 * 4 = 60 : 5 * 4 = (50 + 10) * 4 = (50 : 5 + 10 : 5) * 4 = (10 + 2) * 4 = 10 * 4 + 2 * 4 = 40 + 8 = 48