The ratios r01 and r10 of small to large separations of KIC 2837475 primarily exhibit an increase behaviour in the observed frequency range. The calculations indicate that only the models with overshooting parameter delta_ov between approximately 1.2 and 1.6 can reproduce the observed ratios r01 and r10 of KIC 2837475. The ratios r01 and r10 of the frequency separations of p-modes with inner turning points that are located in the overshooting region of convective core can exhibit an increase behaviour. The frequencies of the modes that can reach the overshooting region decrease with the increase in delta_ov. Thus the ratio distributions are more sensitive to delta_ov than to other parameters. The increase behaviour of the KIC 2837475 ratios results from a direct effect of the overshooting of convective core. The characteristic of the ratios provides a strict constraint on stellar models. Observational constraints point to a star with M=1.490±0.018solar masses, R=1.67±0.01solar radii, age =2.8±0.4 Gyr, and 1.2\lesssim delta_ov \lesssim 1.6 for KIC 2837475.