Question

Un costum de haine costa cat doua uniforme scolare iar o uniforma costa cat cinci camasi .sa se afle pretul fiecarui obiect stiiind ca 40 coatume.150 uniforme si 120 camasi costa impreuna 81280 lei

Answer 1

$a-costum ;b-uniforme;c-camasi \\ a=2b =\ \textgreater \ a=10c\\ b=5c \\ 40a+150b+120c=81280 /:10 \\ 4a+15b+12c=8128 \\ inlocuim \\ 40c+75c+12c=8128 \\ 127c=8128 \\ c=8128:127 \\ c=64.camasi \\ a=10*64=640 .costume \\ b=5*64=320.uniforme \\ \\ verificare:64*120+40*640+150*320=7680+25600+48000 \\ =81280 lei$

Answer 2

h=2u;
u=5c⇒h=2·5c⇒h=10c;
⇒40h+150u+120c=81280lei
⇒40·10c+150·5c+120c=81280;
⇒400c+750c+120c=81280
⇒1270c=81280
⇒c=64[lei-camasa];
⇒h=10·64
⇒h=640[lei-costum de haine];
⇒u=5·64
⇒u=320[lei-uniforma scolara];