Hello everyone. Can anyone help me solve the following problem or give me an idea where to begin. It seems very basic but I can't seem to work it out. Thank you.

"Mr and Mrs Matrix set out one Sunday to jog round the same course.

Mr Matrix runs 4 km/h faster than his wife. He completes the course in 2 hours and she takes 3 hours.

Calculate how fast each person runs and how long the course is."