Question

aflati media aritmetica a trei nr.,stiind ca 2 cate 2 au media aritmetica 14,5,21,4,respectiv11,5.

Answer 1

(a+b):2=14,5⇒a+b=29
(b+c):2=21,4⇒b+c=42,8
(a+c):2=11,5⇒a+c=23
le adunam si rezulta
2(a+b+c)=29+42,8+23
a+b+c=94,8:2
a+b+c=47,4

ma=(a+b+c):3=47,4:3=15,8