Question

Marius a vandut 5/12 din colectis lui de timbre iar carti iau ramas 140 .Cate timbre sunt?

Answer 1

x- colectia de carti

5/12 din x=  5/12 * x=  5x/12- a vandut

x- 5x/12=  (12x-5x)/12=  7x/12 -i-au ramas

7x/12= 140

x=12*140/7

x=12*20

x=240 timbre

Answer 2

12/12-5/12=7/12

$\frac{7}{12} din X=140$

$\frac{7x}{12} =140$

7x=1680
x=240(timbre sunt)