Crime scene: 162 mystery solving puzzles to find out who the murderer is

Chapter 2 The Bicycle Murderer

Inspector Yu runs in the mountains every morning.It was an early morning after the rain, the sky was a little cloudy, but the air was exceptionally fresh.Detective Yu came to the foot of the mountain on his bicycle and prepared to run.Suddenly, he found a policeman on the side of the road with a knife stuck in his abdomen, covered in blood, lying there dying.

Detective Yu hurriedly removed the scarf around his neck to stop the bleeding for the police.

The dying policeman said in a weak voice: "Five or six minutes ago, I saw a man acting suspiciously. I stepped forward to question him. I didn't expect him to kill me, and then he ran away on my bicycle."

After the policeman finished speaking, he pointed his fingers in the direction where the murderer was escaping, and he died in a short while.

Two or three of the nearby houses happened to pass by, so Inspector Yu asked them to take care of the funeral and call the police. He rode on his bicycle and followed the murderer's escape direction to look for clues.

Riding and riding, I came to a double fork. These two roads are gentle slopes, and construction is underway 40 meters away from the intersection, so the road surface is full of sand, gravel and mud.

Inspector Yu first took a look at the fork on the right. On the gravel road, there were obvious traces of bicycle tires.

"The murderer seems to have escaped along this road."

As a precaution, he also checked the pavement of the left fork, where there were also wheel tracks.

"Hmm! In which direction is he running away? Anyway, he will always choose one of the two roads in front of him. Probably the murderer took the opposite road a little while ago, riding uphill or downhill, and walked past the police station. According to the marks left by the front and rear wheels of the two vehicles, it should be immediately clear which road the murderer escaped from."

Inspector Yu compared the wheel marks of the two bicycles in detail with keen observation. "The traces of the road on the right, the front and rear wheels are roughly the same; and the road on the left, why are the traces of the front wheels shallower than the rear wheels? Oh, I see."

So Inspector Yu chased after him.

Can you deduce from which road the Inspector followed?

[Answer] Judging the whereabouts of the murderer based on the traces of the tires.

The murderer escaped along the fork on the right.Because the tire marks left by the front and rear wheels are exactly the same.

Usually, when riding a bicycle, the weight of the rider is added to the rear wheel; therefore, on flat roads or when going downhill, the traces of the front wheels are shallower, and the traces of the rear wheels are deeper.But when going uphill, because the strength of the rider leans forward, and the center of gravity is placed between the pedals and the handlebars of the bicycle, the trace depth of the front wheel and the rear wheel will be exactly the same.

(End of this chapter)