Question

Aflati numarul x , daca media aritmetica a numerelor x, 30 % din x si 60 % din x este egala cu 38.

Answer 1

Ma=(X+30/100X+60/100X)÷3=38 |×3
X+90/100X=114
X+9/10X=114
10X+9X=1140
19X=1140
X=1140÷19
X=60

Answer 2

(x+30%x+60%x):3=38
x(100%+30%+60%):3=38 |·3
x·190/100=38·3 |:19
x·1/10=6
x=60

verificare: (60+30/100·60+60/100·60):3=(60+18+36):3=114:3=38

Numarul x=60