Question 9712
So Lorna drives the moped at 24 kph. After one hour, she will be 24 km away from where she left. (So, Lorna has a 24 km ahead start).


At the moment Lorna reaches the 24 km mark, Allison gets in the car and drives. The problem asks for how far will Allison have to drive to catch Lorna if she has to do it in 1/2 an hour. This means that after the hour that Lorna rode the moped, she will be driving for 1/2 an hour. This would be the same 1/2 hour that Allison will try to catch up. In 1/2 an hour, Lorna would have covered another 12 km (since it's half of 24 km in 1 hour). So, at the time Allison catches up with Lorna, both of them would have traveled 36 km.