When 10 mL of an aqueous solution of $\mathrm{Fe}^{2+}$ ions was titrated in the presence of dil $\mathrm{H}_2 \mathrm{SO}_4$ using diphenylamine indicator, 15 mL of 0.02 M solution of $\mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_7$ was required to get the end point. The molarity of the solution containing $\mathrm{Fe}^{2+}$ ions is $\mathrm{x} \times 10^{-2} \mathrm{M}$. The value of x is $\_\_\_\_$ .
(Nearest integer)