1000 − 39 * 25 − 25 = 1000 − 975 − 25 = 1000 − (975 + 25) = 1000 − 1000 = 0
$\snippet{name: column_multiplication, x: 39, y: 25}$
 
567 : 9 * 12 + 144 = 63 * 12 + 144 = 756 + 144 = 900
$\snippet{name: long_division, x: 567, y: 9}$
 
$\snippet{name: column_multiplication, x: 63, y: 12}$
 
$\snippet{name: op_column, sign: '+', x: 756, y: 144, z: 900}$
 
(480 + 256) : 4 * 5 − 632 : 4 = 736 : 4 * 5 − 158 = 184 * 5 − 158 = 920 − 158 = 762
$\snippet{name: op_column, sign: '+', x: 480, y: 256, z: 736}$
 
$\snippet{name: long_division, x: 736, y: 4}$
 
$\snippet{name: column_multiplication, x: 184, y: 5}$
 
$\snippet{name: long_division, x: 632, y: 4}$
 
$\snippet{name: op_column, sign: '-', x: 920, y: 158, z: 762}$
 
124 * 7 − (1000 − 199) : 9 * 8 = 868 − 801 : 9 * 8 = 868 − 89 * 8 = 868 − 712 = 156
$\snippet{name: column_multiplication, x: 124, y: 7}$
 
$\snippet{name: op_column, sign: '-', x: 1000, y: 199, z: 801}$
 
$\snippet{name: long_division, x: 801, y: 9}$
 
$\snippet{name: column_multiplication, x: 89, y: 8}$
 
$\snippet{name: op_column, sign: '-', x: 868, y: 715, z: 156}$