Alam

# Input Data
Duplex <- c (408, 404, 396, 397, 403, 399, 396, 405, 396, 404, 402, 397, 398, 399, 396, 402, 396, 401, 400, 401, 392, 408,397,400,414,399, 401, 400,404, 401,402,404, 400, 404, 401, 401, 400,411, 398, 404, 400, 405, 407, 404, 401, 400, 394, 401, 402, 390)

# Hitung rata-rata
mean (Duplex)

## [1] 400.9

# Hitung Ragan
var (Duplex)

## [1] 19.72449

#Membentuk tabel frekuensi 
n        <- length (Duplex)
range    <- max(Duplex) - min(Duplex)
sturgess <- 1 + 3.3*log10(n)
kelas    <- round(sturgess)
breaks   <- seq(389, 417,
                length.out =kelas)
as.data.frame(table(cut(Duplex, breaks ))) 

##        Var1 Freq
## 1 (389,394]    2
## 2 (394,398]   11
## 3 (398,403]   23
## 4 (403,408]   10
## 5 (408,412]    3
## 6 (412,417]    1

hist(Duplex, breaks = breaks)