Explicație pas cu pas:
a+b+c=9
a) a/4=b/6=c/8=k
=>a=4k b=6k c=8k
a+b+c=9
4k+6k+8k=9
18k=9
=> k=9/18 = 0,5
a=4k=4×0,5=2
b=6k=6×0,5=3
c=8k=8×0,5=4
b)1/a=3/b=5/c
=> b=3a
c =5a
a+3a+5a=9
9a=9
=>a=9/9=1
b=3a=3×1=3
c=5a=5×1=5
c)a/5=b/10=c/12=k
=>a=5k b=10k c=12k
5k+10k+12k=9
27k=9
=>k=9/27= 0,(3)=0,33...
=>a=5×0,33=1,65
b=10×0,33=3,3
c=12×0,34=4,08
*cu aproximatie
Sper ca te-am ajutat ! :)