dibantu kaka semoga bisa

31 - 35 : xᵢ = 33 , fᵢ = 5 , Maka fᵢxᵢ = 165
36 - 40 : xᵢ = 38 , fᵢ = 7 , Maka fᵢxᵢ = 266
41 - 45 : xᵢ = 43 , fᵢ = 13 , Maka fᵢxᵢ = 559
46 - 50 : xᵢ = 48 , fᵢ = 9 , Maka fᵢxᵢ = 432
51 - 55 : xᵢ = 53 , fᵢ = 6 , Maka fᵢxᵢ = 318

[tex] \sum{f_ix_i} = 165 + 266 + 559 + 432 + 318 = 1740 \\
\sum{f_i} = 40 \\
Maka \ : \\
\overline{x} = \frac{1740}{40} = 43,5 [/tex]