If you run for 0.4 hours at 7 mph, how fast should you walk during the next 0.8 hours to have the average speed of 5 mph?

4 mph

Step-by-step explanation:

The average speed of an object is given by the total distance covered by the time taken:

where

d is the total distance covered

t is the time taken

in the first part, the person runs for 0.4 hours at a speed of 7 mph, so the distance covered in the 1st part is

Then the distance covered in the second part is , so the total distance is

(1)

The total time elapsed is 0.4 hours (first part) + 0.8 hours (second part), so

So we can write the average speed as

(1)

We want the average speed to be 5 mph,

v = 5 mph

Therefore we can rearrange eq.(1) to find d2:

And therefore, the speed in the second part must be

english, cause i can’t you

what is the information provided?

step-by-step explanation: