latihan soal statistika 1

1. STATISTIK 1
Lembar Kerja 7 (Tendensi Sentral)
Nama
NIM
Kelas
Input Data dalam Tabel
Nilai
Interval
ƒ ƒkom Χi Ƒ𝛘i
40 – 48 4 4 44 176
49 – 57 11 15 53 583
58 – 66 18 33 62 1116
67 – 75 29 67 71 2059
76 – 84 21 83 80 1680
85 – 93 10 93 89 890
94 - 100 3 96 97 291
Ʃ 96 Ʃ 6795
1. Mencari Modus
Md = Bb + i (
𝑏1
𝑏1 + 𝑏2
) = 66,5 + 9 (
11
11+8
)
= 66,5 + 9
11
18
= 66,5 + 5, 21 = 71,71
2. Mencari Median
Md = Bb + i (
𝑛− ƒ𝑘𝑜𝑚2
1
ƒ𝑚𝑑
) = 66,5 + 9 (
96− 332
1
29
)
= 66,5 + 9 (
48 −33
29
)
= 66,5 + 9 (
15
29
) = 66,5 + 4,65 = 71,15
3. Mencari Mean ( 𝝌 )
Me =
∑ ƒ𝑖𝑋𝑖
∑ ƒ𝑖
=
6795
96
= 70,78 atau 70,8

2. ƒ Χi (𝑥𝑖 − 𝝌) (𝑥 𝑖 − 𝝌)2
ƒ(𝑥 𝑖 − 𝝌)2
ƒ|𝑥𝑖 − 𝝌|
4 44 -26,8 718,24 2872,96 109,2
11 53 -17,8 316,84 3485,24 195,8
18 62 -8,8 77,44 1393,92 158,4
29 71 0,2 0,04 1,16 5,8
21 80 9,2 84,64 1777,44 193,2
10 89 18,2 331,24 3312,4 182
3 97 26,2 686,44 2059,32 78,6
Ʃ 96 Ʃ 0.4 Ʃ 2214,88 Ʃ 14902,44 Ʃ 923
4. Standar Deviasi
S= √
Ʃƒ(𝑥 𝑖−𝝌)2
Ʃƒ−𝟏
= √
𝟏𝟒𝟗𝟎𝟐,𝟒𝟒
𝟗𝟔−𝟏
= √
𝟏𝟒𝟗𝟎𝟐,𝟒𝟒
𝟗𝟔−𝟏
= √𝟏𝟓𝟔, 𝟖𝟔 =
5. Koevisien Variasi
Kv=
𝒔
𝝌
× 100% =
6. Simpangan rata-rata
Sr =
Ʃ ƒ|𝑥 𝑖−𝝌|
ƒ
=
𝟗𝟐𝟑
𝟗𝟔
= 25,63
7. Kuartil
a. 𝑸 𝟏 = b + P (
𝟏
𝟒
𝒏− Ʃƒ
ƒ
) =
b. 𝑸 𝟐= b + P (
𝟏
𝟐
𝒏− Ʃƒ
ƒ
) =
c. 𝑸 𝟑= b + P (
𝟑
𝟒
𝒏− Ʃƒ
ƒ
) =