Question

pretul unui obiect s.a marit cu 20%. Dupa un anumit timp,noul pret s.a micsorat cu 20%. Dupa cele doua modificari de pret,obiectul costa 2400 lri. Care a fost pretul initial al obiectului?

Answer 1

100%+20%=120%

100-20%=80%
2400=80%
2400:80x100=3000lei
3000:120x100=2500 leia costat

Answer 2

$100$%$+20$%$=120$%
$100-20$%$=80$%
$2400=80$%
$\frac{80}{100}*2400=\frac{2400*100}{80}=\frac{240000}{80}=3000~lei$
$\frac{120}{100}*3000 = \frac{3000*100}{120}=\frac{300000}{120}=2500~lei~a~costat$