Respuesta :

[tex] \dfrac{ 2\dfrac{1}{4} }{ \dfrac{30}{60} } \\ \\ = \dfrac{9}{4} \div \dfrac{30}{60} \\ \\ = \dfrac{9}{4} \times \frac{60}{30} \\ \\ = 4.5[/tex]

4.5 miles per hour.

Hope this helps. - M