In basic medium \( \mathrm{CrO}_{4}^{2-} \) oxidises \( \mathrm{S}_{2} \mathrm{O}_{3}^{2-} \) to form \( \mathrm{SO}_{4}…

In basic medium \( \mathrm{CrO}_{4}^{2-} \) oxidises \( \mathrm{S}_{2} \mathrm{O}_{3}^{2-} \) to form \( \mathrm{SO}_{4}^{2-} \) and itself changes into \( \mathrm{Cr}(\mathrm{OH})_{4}^{-} \). The volume of \( 0.154 \mathrm{M} \mathrm{~CrO}_{4}^{2-} \) required to react with \( 40 \mathrm{~mL} \) of \( 0.25 \mathrm{M} \mathrm{~S}_{2} \mathrm{O}_{3}^{2-} \) is _______ \( \mathrm{mL} \).

(Rounded-off to the nearest integer)