Let there be x articles.Then the production cost of each article =3+2xTotal production cost =x(3+2x)=903x+2x2=902x2+3x−90=02x2+15x−12x−90=02x(x−6)+15(x−6)=0(2x+15)(x−6)=0x=6,−215​Number cannot be negative.  So, number of articles =6 and the cost of each article =Rs.15