Question

daca a+b+c=72 a,b,c sunt direct proportionale cu 5,4,3 aflati a,b,c

Answer 1

a/5=b/4=c/3=(a+b+c)/(5+4+3)=72/12=6
a=5x6=30
b=4x6=24
c=3x6=18

Answer 2

             [tex]a+b+c=72\\ \frac{a}{5} = \frac{b}{4} = \frac{c}{3} =k\\\\ 5k+4k+3k=72\\ 12k=72\\ k=6\\\\ =\ \textgreater \ a=30~;b=24~;c=18\\\\ Proba:20+24+18=72\\ 72=72\\\\ Sau...\\ \frac{a}{5} = \frac{b}{4} = \frac{c}{3} = \frac{a+b+c}{5+4+3} \\\\ \frac{a}{5} = \frac{b}{4} = \frac{c}{3} = \frac{72}{12}\\\\ \frac{a}{5} =6=\ \textgreater \ a=30\\\\ \frac{b}{4}=6=\ \textgreater \ b=24\\\\ \frac{c}{3} =6=\ \textgreater \ c=18 [/tex]