nilai rata rata hitung dari data adalah 34. nilai m adalah ( nilai :, 21-25,26-30,31-35,36-40,41-45,46-50) frekuensi : 2,8,9,m,3,2

Nilai...Titik Tengah=x ...F.......Fx
21-25.............23.............2.......46
26-30............28.............8....224
31-35..............33.............9....297
36-40.............38............m..38m
41-45..............43............3.....129
46-50.............48............2.....96
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Jumlah.....................24+m...792+38m
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Rata-rata = (jumlah Fx)/(jumlah F)
34 = (792+38m)/(24+m)
34(24+m) = 792+38m
816+34m = 792+38m
816 - 792 = 38m - 34m
24 = 4m
m = 24/4
m = 6 (a)