If it takes B hours to walk a certain distance at the rate of 3 miles per hour, the number of hours it takes to return the same distance at 4 miles per hour is...?

4/3 the speed means 3/4 the time.

time = distance/speed

whats the answer then...?

To find the number of hours it takes to walk the same distance at a different rate, you can use the formula:

Time = Distance / Speed

In this case, the distance remains the same, so we can write:

Time1 = Distance / Speed1

Where Time1 represents the time it takes to walk the distance at the initial speed of 3 miles per hour.

Now, we can substitute the given values:

Time1 = Distance / 3

Similarly, to find the number of hours it takes to walk the same distance at a speed of 4 miles per hour, we can write:

Time2 = Distance / Speed2

Where Time2 represents the time it takes to walk the distance at the new speed of 4 miles per hour.

Substituting the values:

Time2 = Distance / 4

Since both Time1 and Time2 represent the time it takes to walk the same distance, we can set them equal to each other:

Distance / 3 = Distance / 4

Now, solving for Distance, we can cross-multiply:

4 * Distance = 3 * Distance

This results in:

4 Distance = 3 Distance

To find the number of hours it takes to return the same distance at 4 miles per hour, we need to determine the value of Distance. However, the information provided in the question does not give us enough information to calculate a specific value for Distance. Therefore, we cannot determine the exact number of hours it takes to walk back at 4 miles per hour.