bantu kakak soal matematika no 5

A.
Nilai
3 = 4orang
4 = 5orang
5 = 8orang
6 = 6orang
7 = 10orang
8 = 5orang
9 = 2orang

Siswa : 4+5+8+6+10+5+2=40 siswa

[tex] (3 \times 4) + (4 \times 5 ) + (5 \times 8) + (6 \times 6) + (7 \times 10) + (8 \times 5) + (9 \times 2) = 236 \div 40 \\ =5.9[/tex]
B. diatas 5.9 =
nilai 6, 7, 8, 9
6, 10, 5, 2 = 23 orang

dibawah rata rata = 40-23=17 orang