Question

calculati media aritmetica ponderata a numerelor rationale pozitive b) 2,75 si 1,3(8) cu pinderile 2 respectiv 9 . clasa 6 multumesc

Answer 1

$\frac{2 \frac{3}{4} \times 2 + 1 \frac{7}{18} \times 9 }{2 + 9} = \frac{ \frac{11}{2} + \frac{25}{2} }{11} = \frac{18}{11}$
Baftă!

Answer 2

2,75 = 275/100 = 55/20
1,3(8) = (138-13)/90 = 125/90 = 25/18

Media ponderata = [(55/20)*2 + (25/18)*9]:(2+9) = (55/10+25/2):11 = (55/10 + 125/10):11= 180/10 : 11 = 18: 11 = 18/11