Question

Se stie ca : a:b=3 b:2=c a-b=40 Afla: 3a-4b+5c

Answer 1

3b=a
2c=b
3a+4b+5c=9b+4b+2b+c=15b+c
a-b=40
40+b=a
3b=40+b
2b=40
b=20
15b+(b/2)=15*40+20=600+20=620

Answer 2

a:b=3=>a=3b
b:2=c=>b=2c
a-b=40=>a=b+40
6c=2c+40
6c-2c=40
4c=40
c=10
a=30
b=20