1. Data Penjualan Pangsit Goreng & Pangsit Basah
Bulan
|
Y
|
X
|
X.Y
|
X²
|
X⁴
|
X².Y
|
Jan
|
4.350
|
-9
|
(39.150)
|
81
|
6.561
|
352.350
|
Feb
|
4.495
|
-7
|
(31.465)
|
49
|
2.401
|
220.255
|
Mar
|
4.650
|
-5
|
(23.250)
|
25
|
625
|
116.250
|
Apr
|
4.960
|
-3
|
(14.880)
|
9
|
81
|
44.640
|
Mei
|
4.900
|
-1
|
(4.900)
|
1
|
1
|
4.900
|
Jun
|
4.930
|
1
|
4.930
|
1
|
1
|
4.930
|
Jul
|
5.100
|
3
|
15.300
|
9
|
81
|
45.900
|
Agst
|
5.115
|
5
|
25.575
|
25
|
625
|
127.875
|
Sept
|
5.220
|
7
|
36.540
|
49
|
2.401
|
255.780
|
Okt
|
5.425
|
9
|
48.825
|
81
|
6.561
|
439.425
|
∑
|
49.145
|
17.525
|
330
|
19.338
|
1.612.305
|
a.
Cari
nilai b
b = ∑xy : ∑x²
= 17.525 : 330
=
53
b.
Eliminasi
a & c (cari nilai c)
∑y= n.a+c.∑x²
∑x².y= ∑x².a+c.∑x⁴
49.145 = 10.a + c. 330 ..........
(*33)
Pengeliminasian
1.621.785 = 330 .a + c. 10.890
1.612.305 = 330.a + c. 19.338 _
9480 = c. -8.448
c =
-1,12
c.
Cari a
49.145 = 10.a + c. 330 .......... (*58,6)
1.612.305= 330 .a + c. 19.338
Pengeliminasian
2.879.897 = 586 . a + c. 19.338
1.612.305 = 330 . a + c. 19.338 _
1.267.592 = a. 256
a =
4951
d. Ramalan Penjualan
Bulan November 2016 s/d April 2017
1.
Bulan November 2016
=
4951 + 53 (11) + (-1,12) . (121)
= 4951 + 583 - 135,52
= 5399
2.
Bulan Desember 2016
Y = a+b(x) + c(x²)
= 4951 + 53 (13)
+ (-1,12) . (169)
= 4951 + 689 -
189,28
= 5451
3.
Bulan Januari 2017
Y = a+b(x) + c(x²)
= 4951 + 53 (15)
+ (-1,12) . (225)
= 4951 + 795 -
252
= 5494
4.
Bulan Februari 2017
Y = a+b(x) + c(x²)
= 4951 + 53 (17)
+ (-1,12) . (289)
= 4951 + 901
-323,68
= 5528
5.
Bulan Maret 2017
Y = a+b(x) + c(x²)
=
4951 + 53 (19) + (-1,12) . (361)
= 4951 + 1007 -404,32
= 5554
6.
Bulan April 2017
Y = a+b(x) + c(x²)
= 4951 + 53 (21)
+ (-1,12) . (441)
= 4951 + 1113 -493,92
3. Grafik Peramalan Penjualan 6 Bulan kedepan (November 2016 s/d April 2017)
Selanjutnya yaitu menghitung Anggaran Penjualan tiap Bulan berdasarkan peramalan sebelumnya.
Dan berikut adalah Anggaran Penjualan Pangsit tiap bulan untuk 6 bulan kedepan (November 2016 s/d April 2017)

















