a)
In order to find Kyle's speed in miles per hour, we just need to divide the amount of miles he walked by the amount of time it took:
[tex]\text{speed}=\frac{\frac{1}{2}}{\frac{1}{4}}=\frac{1}{2}\cdot4=2\text{ mph}[/tex]b)
In order to calculate the LCM of 2 and 4, let's factor them in their prime factors:
[tex]\begin{gathered} 2\to2 \\ 4\to2\cdot2 \end{gathered}[/tex]The LCM is the product of each prime factor the maximum number of times they appear in a single number, so we have LCM = 2 * 2 = 4.
Multiplying 1/2 and 1/4 by 4, we have:
[tex]\begin{gathered} \frac{1}{2}\cdot4=2\text{ miles} \\ \frac{1}{4}\cdot4=1\text{ hour} \end{gathered}[/tex]So in one hour he walks 2 miles, so his speed is 2 miles per hour.
