30 квадратов-100%
10 квадратов- x%
x=10*100/30=33.3%(D)
620000:10=62000
620000:100=6200
620000:1000=620
620000:10000=62
1) 3966*56=222096
2) 89*62=5518
3) 222096-5518=216578
Ответ; 216578
2 * (23 + х) - 4 = 36
46 + 2х - 4 = 36
2х + 42 = 36
2х = 36 - 42
2х = -6
х = -6 : 2
х = -3
Вот чертеж...............