Răspuns:
15% + 25% + 20% + 10% = 70%
fie e - nr. elevilor
70/100 * e = 28
e = 2800/70
e= 40
=> 40 de elevi
5/100 * 40 = 2 elevi care au obtinut nota 3
5/100 * 40 = 2 elevi care au obtinut nota 4
10/100 * 40 = 4 elevi care au obtinut nota 5
10/100 * 40 = 4 elevi care au obtinut nota 6
15/100 * 40 = 6 elevi care au obtinut nota 7
25/100 * 40 = 10 elevi care au obtinut nota 8
20/100 * 40 = 8 elevi care au obtinut nota 9
10/100 * 40 = 4 elevi care au obtinut nota 10
Mp =(2*3 + 2*4 + 4*5 + 4*6 + 6*7 + 10*8 + 8*9 + 4*10)/(2+2+4+4+6+10+8+4)
Mp =(6+8+20+24+42+80+72+40)/40
Mp = 292/40
Mp = 7,3
