Question

la o lucrare de control elevii unei clase au obtinut urmatoarele note
10-10%
9-20%
8-30%
7-20%
6-10%
5-10%
Stiind ca un numar de 24 de elevi aun obtinut note de la 8 in sus, aflati cati elevi sunt in clasa si care a fost media pe clasa.

Answer 1

(10+20+30)%.................24 e.

60%.......................24e
100%.......................x

x=24*100 /60= 40 e. = total elevi.


nota5: 10/100*40= 4 e
nota6: 10/100*40=4 e
nota7: 20/100*40= 8 e
nota8: 30/100*40= 12 e.
nota9: 20/100*40= 8 e
nota10:10/100*40= 4 e

M= (4*5+ 4*6+8*7+12*8+8*9+4*10)÷ 40= 308÷40= 7, 7