Answer: [tex]1\dfrac56\text{ miles per hour.}[/tex]
Step-by-step explanation:
Given: Total distance traveled = [tex]5\dfrac12\text{ miles}[/tex]
[tex]=\dfrac{2\times5+1}{2}\text{ miles}\\\\=\dfrac{11}{2}\text{ miles}[/tex]
They started at 11 A.M at cam back at 1 PM , that means it took 3 hours to cover [tex]\dfrac{11}2[/tex] miles.
Now, [tex]speed=\dfrac{distance}{time}[/tex]
[tex]\Rightarrow\ speed =\dfrac{\dfrac{11}2}{3}=\dfrac{11}{6}\\\\=\dfrac{6\times1+5}{6}\\\\=1\dfrac56\text{ miles per hour.}[/tex]
Hence, the average speed of walking speed = [tex]1\dfrac56\text{ miles per hour.}[/tex]
