Question

"aflati numaryl x,y,z,stiind ca xsupralui 2 = y supralui 5= z supralui 9 stind ca x+y+z=80."

Answer 1

x/2=y/5=z/9=k
⇒x/2=k⇒x=2k;
⇒y/5=k⇒y=5k;
⇒z/9=k⇒z=9k;
⇒x+y+z=80
⇒2k+5k+9k=80
⇒16k=80
⇒k=5;
⇒x=2·5⇒x=10;
⇒y=5·5⇒y=25;
⇒z=9·5⇒z=45;