At $\mathrm{t}=0$, a body of mass 100 g starts moving under the influence of a force $(\hat{5} \mathrm{i}+1 \hat{0} \mathrm{j}) \mathrm{N}$ from the origin. After 2 s its position is $(2 \hat{x} \mathrm{i}+5 \hat{y} \mathrm{j}) \mathrm{m}$. The ratio $\mathrm{x}: \mathrm{y}$ is $\_\_\_\_$ .