The sum we split in the parts by proportion $$S_a:S_b:S_c=1:1/5:1/2$$ $$S_a+S_b+S_c=600$$ $$S_a/1=S_b/(1/5)=S_c/(1/2)=k$$ $$k+k/5+k/2=600$$ $$k=6000/17=352,94$$ $$S_a=352,94,S_b=70,58,S_c=176.47$$
The sum we split in the parts by proportion $$S_a:S_b:S_c=1:1/5:1/2$$ $$S_a+S_b+S_c=600$$ $$S_a/1=S_b/(1/5)=S_c/(1/2)=k$$ $$k+k/5+k/2=600$$ $$k=6000/17=352,94$$ $$S_a=352,94,S_b=70,58,S_c=176.47$$