tentukan nilai a + b + c , jika a -b = 24 ; a : b = 5 : 2 dan c 1/7 (a + b)

Jawaban :

Dari pers (2) a : b = 5 : 2
Maka b = 2/5 a

Subtitusikan ke pers (1)
a - b = 24
a - 2/5a = 24
3/5a = 24
a = 40
b = 2/5 a = 2/5.40 = 16
c = 1/7 (a+b) = 1/7 (40+16) = 56/7 = 8

Maka a + b +c = 40 + 16 + 8 = 64

Semoga Bermanfaat :)

a:b = 5:2
a=5/2 b

5/2b - b = 24
3/2 b = 24
3b = 48
b= 16

a-b = 24
a-16= 24
a= 24+16
a= 40

c= 1/7( a+b)
  =1/7 (40+16)
  =1/7  ( 56)
  = 8

a+b+c= 40+ 16+ 8 = 64