Răspuns :
x-pretul bicicletei
aflam cu cat s-a marit pretul
x+20/100*x
x+x/5 aducem la acelasi numitor
5x+x supra 5=6x/5 (noul pret)
aflam cu cat s-a scumpit
6x/5+10/100*6x/5
6x/5+3x/25 aducem la acelasi numitor
30x+3x supra 25=33x/25
33x/25=264
x=264*25 supra 33
x=8*25
x=200
aflam cu cat s-a marit pretul
x+20/100*x
x+x/5 aducem la acelasi numitor
5x+x supra 5=6x/5 (noul pret)
aflam cu cat s-a scumpit
6x/5+10/100*6x/5
6x/5+3x/25 aducem la acelasi numitor
30x+3x supra 25=33x/25
33x/25=264
x=264*25 supra 33
x=8*25
x=200
(x + [tex] \frac{20}{100}x [/tex]) pretul dupa scumpirea de 20%
(x + [tex] \frac{20}{100}x [/tex]) + [tex] \frac{10}{100} [/tex](x + [tex] \frac{20}{100}x [/tex]) - pretul dupa scumpirea de 10%
(x + [tex] \frac{20}{100}x [/tex]) + [tex] \frac{10}{100} [/tex](x + [tex] \frac{20}{100}x [/tex]) = 264
[tex](x + \frac{x}{5}) + \frac{x + \frac{x}{5}}{10} =264[/tex] /·10
[tex]10x + 2x + x + \frac{x}{5} = 2640 [/tex]
[tex]13x + \frac{x}{5} = 2640[/tex] /·5
[tex]65x + x = 13200[/tex]
[tex]66x = 13200[/tex]
[tex]x=200[/tex]
(x + [tex] \frac{20}{100}x [/tex]) + [tex] \frac{10}{100} [/tex](x + [tex] \frac{20}{100}x [/tex]) - pretul dupa scumpirea de 10%
(x + [tex] \frac{20}{100}x [/tex]) + [tex] \frac{10}{100} [/tex](x + [tex] \frac{20}{100}x [/tex]) = 264
[tex](x + \frac{x}{5}) + \frac{x + \frac{x}{5}}{10} =264[/tex] /·10
[tex]10x + 2x + x + \frac{x}{5} = 2640 [/tex]
[tex]13x + \frac{x}{5} = 2640[/tex] /·5
[tex]65x + x = 13200[/tex]
[tex]66x = 13200[/tex]
[tex]x=200[/tex]