Question

exercitiul 7 va rog ajutati-ma

Answer 1

Notez cu p pretul initial.

→Pretul a crescut cu 20% :

$x + \frac{20x}{100} = x + \frac{2x}{10} =\frac{12x}{10}=\frac{6x}{5}$

→Noul pret a crescut cu 15% :

$\frac{6x}{5}+\frac{15}{100} *\frac{6x}{5} = \frac{6x}{5}*\frac{18x}{100} =\\\\\frac{6x}{5} + \frac{9x}{50} = \frac{69x}{50}$

→Dupa cele doua cresteri:

$\frac{69x}{50} = x + 760$

$69x = 50x + 760 * 50$

$19x = 760 * 50$

$x=\frac{760*50}{19} = 40 * 50 = 2000lei$

⇒ x = 2000 lei ( pretul initial )

Pretul dupa prima scumpire :

$2000 + \frac{20*2000}{100} = 2000 + 20*20 = 2000+400=2400lei$