Question

Уравнение помогите
n+(n-10) + (n-20)=270

Answer 1

n + (n - 10) + (n - 20) = 270
n + n - 10 + n - 20 = 270
3n = 270 + 30
3n = 300
n = 100

Answer 2

n+n-10+n-20=270
n+n+n=270+10+20
3n=300
n=300:3
n=100