You have the following points for the relation between minutes and miles respectively:
(4 , 22)
(8, 44)
In order to calculate the constant of porportionality use the formula:
m = (y2 - y1)/(x2 - x1)
where (x1,y1) and (x2,y2) are the given points:
m = (44 - 22)/(8 - 4)
m = 22/4
m = 5.5
Hence, the constant of proportionality is 5.5
THe meaning of the point (4 , 22) is:
4 means 4 miles and 22 means 22 minutes. That is, it has been traveled 4 miles in 22 minutes.