Question No.13 :John is driving due east at a constant speed of 72 mph and Jane is driving due west at a constant speed of 56 mph. They leave at the same time from the same place.

Quantity A:The amount of time it takes for there to be a distance of 300 miles between John and Jane

Quantity B: 140 minutes

##we don’t have the original x distance between them so I chose d, but in the solutions, Greg took 300 miles and got 140.625 mins(chose A). Which is correct?