Speed = Distance ÷ Time.<br><br>
&bull; Distance ratio X : Y = 5 : 3<br>
&bull; Time ratio X : Y = 2 : 3<br>
&bull; Speed of X = \(\frac{5}{2}\) = 2.5 units<br>
&bull; Speed of Y = \(\frac{3}{3}\) = 1 unit<br>
&bull; Ratio X : Y = 2.5 : 1 = 5 : 2<br><br>
Final Answer: 5 : 2