Correct answer is : 3
\( \mathrm{r}=\mathrm{K}[\mathrm{A}]^{\mathrm{x}}[\mathrm{B}]^{\mathrm{y}} \)
\((\mathrm{I}) \,6 \times 10^{-3}=\mathrm{K}[0.1]^{\mathrm{x}}[0.1]^{\mathrm{y}} \)
\((\mathrm{IV}) \,2.4 \times 10^{-2}=\mathrm{K}[0.4]^{\mathrm{x}}[0.1]^{\mathrm{y}}\)
\((\mathrm{IV}) /(\mathrm{I})\)
\(4=(4)^{\mathrm{x}} \)
\(\mathrm{x}=1\)
\(\mathrm{r}=\mathrm{K}[\mathrm{A}]^{\mathrm{x}}[\mathrm{B}]^{\mathrm{y}}\)
\(\text {(III) } 2.88 \times 10^{-1}=\mathrm{K}[0.3]^{\mathrm{x}}[0.4]^{\mathrm{y}}\)
\(\text {(II) } 7.2 \times 10^{-2}=\mathrm{K}[0.3]^{\mathrm{x}}[0.2]^{\mathrm{y}}\)
\((III)/(II)\)
\(4=2^y\)
\( y=2\)
Overall order = x + y = 1 + 2 = 3