Tolong jawab dengan benar

misal
surabaya post = x
jawa post = y

x + y = 415 |×5.000
5.000x + 6.000y = 2.230.000
maka
5.000x + 5.000y = 2.075.000
5.000x + 6.000y = 2.230.000
----------------------------------------------(-)
- 1.000y = - 155.000
y = 155
subtitusi ke pers :
x + y = 415
x + 155 = 415
x = 415 - 155
x = 260

jadi surabaya post = x = 260 ( C )