Question

Dupa doua cresteri consecutive de preturi, prima de 10%, a doua de 12%, un telefon mobil costa 739,2 lei. Cat a costat telefonul inainte de cele 2 cresteri?

Answer 1

112% ........................................739,2
100%.........................................x
$\frac{112}{100} = \frac{739,2}{x}$ ⇒ x=$\frac{100×739,2}{112}$=$\frac{73920}{112} =$ 660
110% ........................................660
100% ........................................y
$\frac{110}{100} = \frac{660}{y}$ ⇒ y=$\frac{100×660}{110}$=$\frac{66000}{110}$=600
Raspuns: la inceput, telefonul costa 600 de lei.

Answer 2

112%......739,2
100%......x
x=660
660......110%
y..../......100%
y=600