In a chemical equilibrium the rate of a backward reaction is 7.5*10^-4​ and equilibrium constant is 1.5. So the rate constant of the forward reaction is 

Dear student

In this particular question, we have been given the values of the rate constant of the backward reaction as 7.5x10-4. Also we have been given the value of equilibrium constant as Keq = 1.5. Now we can use the formula for the relation between the equilibrium constant and the rate constants.
The formula here is:
$$\begin{gathered} Keq = \frac{kf}{kb} \\ 1.5 = \frac{kf}{7.5\times {10}^{-4}} \\ thus kf = 1.5\times 7.5\times {10}^{-4} = 1.125\times {10}^{-3} \end{gathered}$$

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