tlng bntu jwb ya kakkk.... bsok dikumpalkan terima kasih

4 siswa = 5
5 = 6
9 = 7
6 = 8
10 = 9
6 = 10

Banyak Siswa = 4 + 5 + 9 + 6 + 10 + 6 = 40 siswa

Nilai :

= ( 4 × 5 ) + ( 5 × 6 ) + ( 9 × 7 ) + ( 6 × 8 ) + ( 10 × 9 ) + ( 6 × 10 )

= 20 + 30 + 63 + 48 + 90 + 60
=311

Rata - rata :
311 : 40 = 7,775

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Mungkin yang dimaksud 80 orang bukan 8 orang karena jika 8 orang gak ada isinya _-

Basket 1 = 135°
Basket 2 = 108 °
Renang = 45°
Voly =
= 360 - ( 135 + 108 + 45 )
= 360 - 288
= 72°

Basket 1 = 135/360 × 80 = 30 orang
Basket 2 = 108/360 × 80 = 24 orang
Voly = 72/360 × 80 = 16 orang

Jumlah siswa : 30 + 24 + 16 = 70 siswa