This was from section 1 of the 2022 Ocotber BMAT paper-question 28. I cannot figure out how to answer this.
Karl is racing against Frank. The race is run over a distance of 800m.
In the first race, Karl allows Frank to start 5 seconds before him, but he still completes the race 3 seconds before Frank.
In the second race, they start to run at the same time, but Karl allows Frank to start 100m ahead of him on the track, so Frank only has to run 700m. Frank completes this race 4.5 seconds before Karl.
In the third race, they again start to run at the same time and Karl allows Frank to start 40m ahead on the track.
Karl runs each race at the same constant speed. Frank runs slower but at the same constant speed for each race.
What is the outcome of the third race?
A) Karl finishes the race 3 seconds before Frank.
B) Karl Finishes the race 0.5 seconds before Frank.
C) They finish the race at the same time.
D) Frank finishes the race 0.5 seconds before Karl.
E) Frank finishes the race 3 seconds before Karl.
According to the answer key, the answer is A, and I've tried to work it out again, but keep getting C 😭. Can someone please explain how to do this?