Răspunsuri

2014-11-17T12:33:26+02:00

(a+15)/2=12
a+15=12 ·2
a=24-15=9

(x+81)/2=70
x=70 · 2-81
x=69
1 5 1
2014-11-17T12:52:46+02:00
Media aritmetica=(a+b)/2
x este numarul cautat
(x+15)/2=12
x+15=2*12
x+15=24
x=24-15
x=9

(x+81)/2=70
x+81=2*70
x+81=140
x=140-81
x=59