Rajeev is trapped atop a building 200m high. He has with him a rope 150m long.There is a hook at the top where he stands.
Looking down, he notices that midway between him and the ground, at a height of 100m, there is a ledge with another hook. In his pocket lies a Swiss knife.
How might he be able to come down using the rope, the two hooks and the Swiss knife?
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