Question

Calculati media aritmetica ponderata a numerelor 2 3/4,3 4/5,4 5/6, cu ponderile 4, 5 si respectiv 6.

Answer 1

$\frac{4* \frac{23}{4}+5* \frac{34}{5} +6* \frac{45}{6} }{4+5+6} (simlplificam~ce~putem~adica~4~cu~4 , 5~cu ~5~si~ 6~cu~6\\\\= \frac{ 23+34+45 }{15} \\\\ = \frac{102}{15} \\\\ \boxed{=6,8}.$