Answer:
2 miles per hour
Step-by-step explanation:
Remember that
[tex]1\ hour=60\ minutes[/tex]
To convert minutes to hours divide by 60
To find out Walter's biking rate, divide the total distance by the total time
so
[tex]\frac{1}{2} :15[/tex]
convert minutes to hours
[tex]\frac{1}{2} :\frac{15}{60}=\frac{60}{30}=2\ \frac{miles}{hour}[/tex]