tolong ya besok di kumpulkan

statistik

38.
nilai.: 60...70...80...90...100
f.......:1......1.....4.....1....3

jumlah nf = 60+70+320+90+ 300 = 840
jumlah f = 1+1+4+1+3 = 10
X rata rata  = 840/10 = 84

39. data di urutkan dari kecil ke besar
60, 70, 70, 80,80..||..,80, 90,90, 100, 100
..........................Median
Me = (80 +80)/2 = 80

nilai rata rata :
60 . 1 =   60
70 . 4 = 280
80 . 1 =   80
90 . 3 = 270

60 + 280 + 80 + 270 = 690 : 9 = 76,44