快猫短视频

#196 Champion trainer

Set by Howard Williams

Three top racehorse trainers, Kate Winsalot, Britney Spurs and Harry Trotter, were invited to compete in the prestigious Champion Trainers Stakes.

Each had to enter three horses in the race, with points being awarded to the trainer according to the finishing position of their mounts. The trainer of the winning animal would be awarded 9 points, the second placed horse 8 points, and so on, down to 1 point for the trainer of the last horse. The person receiving the most points is the Champion Trainer.

The results of the race were delayed waiting for Bored Bronco, one of Harry鈥檚 horses, to finally finish and also because two of Kate鈥檚 runners had to have their positions determined by photograph, with her third horse finishing further back.

When the scores were calculated, it turned out that the three trainers had tied on points. Which trainer鈥檚 horse came first?

Solution next week

#195 Shuttle space

Solution

Bart should drop the three friends 1 kilometre from the pizzeria. We know Jeff walks a certain distance and is then driven the rest of the way. The three friends are driven and then walk. Since the walking and driving speeds are fixed, to arrive at the same time, Jeff and the three friends must walk the same distance (A). Call the distance between the drop-off point and pick-up point B.

We know that A+B+A = 5km. The distance the car drives between setting off and picking up Jeff is A+2B and this is seven times as far as Jeff walks, so A+2B=7A. Hence 2B=6A, ie B=3A. This means 3A +2A=5km so A=1km. Bart drives 4 kilometres, drops his friends, drives back to pick up Jeff and then drives to the pizzeria.