Chemical Kinetics

For the reaction,

\(\mathrm{CH}_3 \mathrm{Br}_{(\mathrm{aq})}+\mathrm{OH}_{(\mathrm{aq})}^{-} \longrightarrow \mathrm{CH}_3 \mathrm{OH}_{(\mathrm{aq})}+\mathrm{Br}_{(\mathrm{aq})}^{-}\)

rate of consumption of $\mathrm{OH}_{(\mathrm{aq})}^{-}$is $\mathrm{x} \mathrm{mol} \mathrm{dm}{ }^{-3} \mathrm{~s}^{-1}$
What is the rate of formation of $\mathrm{Br}_{(9 q)}^{-}$?