Calculate molarity of 9.8% (w/w) solution of H2SO4 if the density of the solution is 1.02g/l?

Since density is already given in  g/l you need not to convert it .
so the calculation is as follows:

Molarity = (Percentage compostion x specific gravity or density )/ (molar mass)

Molarity = (98 x 1.02) / (9.8 x 100 )  =  0.102 M