One day, Detective M was walking on a main street. The case truly lived up to the saying 'fast when it's said to be slow': an old lady's bag was snatched by two robbers riding motorcycles right in front of everyone, and the old lady fell to the ground. Detective M's first reaction was not to chase the criminals, but to take the old lady to the hospital for a checkup. Later, Detective M was commissioned by the old lady to retrieve the stolen bag...
Detective M went to a park not far from the scene and, hidden in some bushes, discovered the motorcycle used by the criminals during the robbery. However, this motorcycle had been stolen from someone else, so even if they found the owner, it wouldn't lead them to the criminals, indicating that these two were habitual offenders.
On the motorcycle, clothes changed by the criminals were also found. Except for the shoes, all other clothes had been replaced, showing the criminals' cunning. Detective M wanted to take some statements, and he saw two young men sitting on a park bench, so he walked over and asked: 'Have you seen anyone in the bushes doing anything?' One young man replied: 'No, we have been here for an hour.' Detective M looked at a puddle on the ground and thought to himself: 'The weather is clear today; it hasn't rained.' Detective M then looked at the young men's hands, suddenly realized something, and said: 'You two are the criminals who just committed the robbery!' The other young man said: 'You... what evidence do you have to claim we are the robbers!?' Detective M: 'Hm? Aren't you?' The faces of the two young men turned pale, and they lowered their heads to confess their crimes.
Question: How did Detective M figure out that the two young men were the robbers? There are three points. One is very simple: Detective M simply said that they were the criminals, and the young men admitted they were robbers. Find the other two points.
Something came up tonight, so the questions are given in advance. Reasoning Group - Reasoning Questions
Replies (10)
Answer revealed: When Detective M asked the young man a question, the young man replied, 'No, we've been here for an hour.' He is lying, or perhaps the incident happened within an hour, and he said 'an hour' to create an alibi. It would have been impossible for them there to have not seen a motorcycle enter the grass. If it happened an hour ago, looking at his hands, he shouldn't have been wearing a watch, yet he clearly said they arrived an hour ago, which proves he is lying. The puddle on the ground was used to clean the mud off his shoes. Finally, saying he was the culprit, and even more so that he mentioned the robber, is practically a self-incrimination.
Only found a little: the puddle of water on the ground is dew in the grass, proving that they had been in the grass.
Another point might be that the criminal has marks on his hands, after all, he was riding a motorcycle to snatch a bag.
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