60/(m+3) miles
Step-by-step explanation:
We begin by finding the speed at which Jenny is walking;
Speed = distance / time
= 4 miles / m+3 minutes
= 4/(m+3) miles / minute
If she is walking at 4/(m+3) miles / minute, how many miles will she cover in 15 minutes;
= 4/(m+3) * 15
= 60/(m+3) miles
Learn More:
For more on speed and distance check out;
https://brainly.com/question/12626613
https://brainly.com/question/13079625
#LearnWithBrainly
