:

78000: 78 = 1000
750 + 250 = 1000
764 + 361 = 1122
8 × 125 = 1000
634 = 366 = 1000
287 - 53 = 234
4565 - 3565 = 1000
561 + 167 = 728
1024 - 224 = 800
17 + 48 = 119
21 × 11 = 231
48 × 0 = 0
5 + 40 = 45
5318 - 4098 = 1220
15 : 2,14 = 7
34 - 34 = 0
171 + 342 = 513
38: 2,71 = 14
1710 - 1425 = 1710
175: 5 = 35
324: 6 = 54
640 : 40 = 16