Question

Nilai matematika dlm stu kelas 72 sdngkan rta" nilai pria 69 dan.wanita 74 jika banyak siswa dalam kelas 40 orang bnyk siswa pria berapa

Answer 1

Rata"kelas(Xk) = 72
rata" pria(Xp) = 69
rata" wanita(Xw) = 74
p+w = 40
w = 40-p

Xk = (Xp.p+Xw.w) / (p+w)
72 = (69.p + 74.(40-p)) / 40
72.40 = 69p + 2960 - 74p
2880 - 2960 = -5p
-80 = -5p
p = 16
banyak pria = 16 orang