Реши уравнения: 388 + x = 840; x · 18 = 72; x − 244 = 256; x : 16 = 6; x · 13 = 91; 720 : x = 9.

1. 388 + x = 840
   x = 840 − 388
   x = 452.
2. x · 18 = 72
   x = 72 : 18
   x = 4.
3. x − 244 = 256
   x = 256 + 244
   x = 500.
4. x : 16 = 6
   x = 6 · 16
   x = 96.
5. x · 13 = 91
   x = 91 : 13
   x = 7.
6. 720 : x = 9
   x = 720 : 9
   x = 80.

Ответ: 452; 4; 500; 96; 7; 80.