200 cc of x × 10^-3 M potassium dichromate is required to oxidise 750 cc of 0.6 M Mohr's salt solution in acidic medium. Here x= ____.

$\displaystyle 200$ cc of $\displaystyle x \times 10^{-3} \mathrm{M}$ potassium dichromate is required to oxidise $\displaystyle 750$ cc of $\displaystyle 0.6$ M Mohr's salt solution in acidic medium.Here $\displaystyle x=$ $\displaystyle \_\_\_\_$.