Условие:

Реши уравнения:
20007 − x = 20000;
x − 900 = 1000;
x + 200 = 3200;
300 + x = 5400.

20007 − x = 20000
x = 2000720000
x = 7
 
x − 900 = 1000
x = 1000 + 900
x = 1900
 
x + 200 = 3200
x = 3200200
x = 3000
 
300 + x = 5400
x = 5400300
x = 5100