Perbandingan uang siti dan ahmad 2:3, sedangkan perbandingan uang ahmad dan sulton 4:5. Jika jumlah uang mereka bertiga Rp700.000,00, maka jumlah uang siti dan

uang siti = a
uang ahmad = b
uang sulton = c
a : b = 2: 3
b : c = 4 : 5
a + b + c = 700.000
a=? , c = ?
jawab :
a: b = 2:3 » b = 3/2 (a) ....... persamaan 1
b: c = 4:5 » b = 4/5 (c)....... persamaan 2

subtitusi
3/2(a) = 4/5(c)
a= 8/15 (c)

a + b + c = 700.000
8/15(c) + 4/5(c) + c = 700.000
(8+12+15)c/15 = 700.000
35C/15 = 700.000
7C/3 = 700.000
7c= 2.100.000
C = 2.100.000÷7 = 300.000

# a + b + c = 700.000
a+ b + 300.000 = 700.000
a+b = 700.000-300.000
a + 3/2(a) = 400.000
5/2(a) = 400.000
5a = 800.000
a = 800.000÷5 = 160.000

uang siti = 160.000
uang sulton = 300.000
uang ahmad = 700.000 - (160.000+300.000) = 700.000 - 460.000
= 240.000

semoga membantu ::)))