To solve this problem, we need to calculate the total time it takes to run 4 miles to your friend's house and then walk the 4 miles back home.

Step 1: Calculate the time taken to run to the friend's house.

The formula for time is:

$\text{Time} = \frac{\text{Distance}}{\text{Speed}}$

Given:

• Distance = 4 miles
• Speed = 7 miles per hour

$\text{Time to run} = \frac{4 \text{ miles}}{7 \text{ miles per hour}} = \frac{4}{7} \text{ hours} \approx 0.571 \text{ hours}$

Step 2: Calculate the time taken to walk back home.

Given:

• Distance = 4 miles
• Speed = 3 miles per hour

$\text{Time to walk} = \frac{4 \text{ miles}}{3 \text{ miles per hour}} = \frac{4}{3} \text{ hours} \approx 1.333 \text{ hours}$

Step 3: Calculate the total time for the round trip.

Now, add the time taken for both the running and walking:

$\text{Total time} = \frac{4}{7} \text{ hours} + \frac{4}{3} \text{ hours} \approx 0.571 \text{ hours} + 1.333 \text{ hours} = 1.904 \text{ hours}$

Step 4: Convert the total time to minutes (if necessary).

To convert hours to minutes:

$1.904 \text{ hours} \times 60 \text{ minutes per hour} \approx 114.24 \text{ minutes}$

So, the total time spent is approximately 1.904 hours or 114.24 minutes.

Would you like further details or have any questions?

Here are 5 related questions for further exploration:

1. What is the average speed for the entire round trip?
2. How much time would it save if you ran both ways at 7 miles per hour?
3. If you reduced your walking speed to 2 miles per hour, how much longer would the return trip take?
4. How far would you travel if you increased the distance by 50%?
5. How long would the trip take if you walked the entire distance at 3 miles per hour?

Tip: When dealing with distance, speed, and time, always ensure that the units are consistent to avoid calculation errors.