Question

Subiectul II problema 2
Am atasat problema in pdf

f6c85a5512758a1620e065c1d30ec7ea.pdf

Answer 1

{ a,b} invers prpportional {1/3 ;1/4}=>
{a,b} direct proportional{ 3;4} => a =3k si b=4k
2*3k+ 384k=3240
6k+12k=3240
18k=3240
k=180 
daca k=180  si a= 33k ; b=4k => a=540 si b=720.

Answer 2

$a* \frac{1}{3}= b*\frac{1}{4} \Leftrightarrow \frac{a}{3}= \frac{b}{4} \Rightarrow a=3k~si~b=4k. \\ \\ 2a+3b=3240 \Leftrightarrow 6k+12k=3240 \Leftrightarrow 18k=3240 \Rightarrow k= 180. \\ \\ a=3k=3*180=540. \\ b=4k=4*180=720. \\ \\ Solutie: (a,b)=(540;720).$