x-pretul initial
4/100*x=4x/100=>cu cat se scumpeste prima oara
10/100*4x/100=40x/10000=>cu cat se scumpeste a doua oara
x+4x/100+40x/10000=14300(aducem la acelasi numitor si anume 10000)
(10000x+400x+40x)/10000=143000000/10000 |*10000
10000x+400x+40x=143000000
10400x=143000000
x=143000000/10400
x=13750 pretul initial
si problema 2 e la fel