dijawab dengan benar ya pake cara...!

11.
mean
=5x4+6x6+7x10+8x9+9x6+10x5/40
=20+36+70+72+54+50/40
=252/40
=6,3
modus
=7
median
=n+1/2
=40+1/2
=41/2
=20,5

no.11 aja dulu..
mean :
f
4  x 5 =   20
6  x 6=    36
10 x7 =   70
9  x8=    72
6  x9=    54
5  x 10 = 50 +
40          302

mean : 302 = 7,55
            40 

modus (yang paling banyak muncul) : 7
median : 7