If f₁, f₂ and f₃ are the fraction of oxygen molecules at 27⁰ C having speed 100 m s^-1 , 200 m s^-1 and 300 m s ^-1 respectively then,

The most probable speed of oxygen molecules at 27⁰ C is $u_{\mathrm{mp}}=\sqrt{\frac{2RT}{M}}={\left(\frac{2\left(8.314{\mathrm{JK}}^{-1}{\mathrm{mol}}^{-1}\right)\left(300\mathrm{K}\right)}{0.032\mathrm{kg}{\mathrm{mol}}^{-1}}\right)}^{1/2}=394.8{\mathrm{ms}}^{-1}$

The fraction of molecules increases with increases in speeds prior to the most probable speed.