Răspuns :
x-pret initial
x+20/100x=24
x+x/5=24
se amplifica prima fractie cu 5
5x/5+x/5=24
6x/5=24
6x=120
x=20
x-pretul initial
20% din x= 20/100*x= 1/5 *x= x/5 -scumpirea
x+x/5= (5x+x)/5=6x/5-noul pret
6x/5=24
x=24*5/6
x=4*5
x=20
20% din x= 20/100*x= 1/5 *x= x/5 -scumpirea
x+x/5= (5x+x)/5=6x/5-noul pret
6x/5=24
x=24*5/6
x=4*5
x=20