Question

Stiind ca :7caiete,3pixuri, 5 radiere costa 2842de bani<br />
2caiete, 5 pixuri si 2radiere costa 1260bani, iar<br />
9 caiete ,8pixuri si 3 radiere costa 3982bani, sa se afle cat costa fiecare obiect.<br />
(100bani=1leu)

Answer 1

7c+3p+5r=2842
2c+5p+2r=1260
9c+8p+3r=3982

7c+3p+5r=2842  +
2c+5p+2r=1260
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9c+89+7r=4102


9c+89+7r=4102      -
9c+8p+3r=3982
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/ + /  4 r = 120; 1r=30

 7c+3p+5*30=2842;       7c+3p= 2842-150;       7c+3p=2692
2c+5p+2*30=1260;        2c+5p =1260-60;         2c+5p =1200


7c+3p=2692      | *2
2c+5p =1200     | *7       

14c+35p=8400 -
14c+6p  =5384
-----------------------
/     29p= 3016;   1p=104   


7c+3p+5r=2842;  1p=104; 1r=30
7c+3*104+5*30=2842
7c=2842- 312-150
7c=2380
c=340

S: 1 c=340; 1p=104; 1r=30