You must raise the weight to a height of 10 meters. you cannot do it! thinking back to what you have learned in science class, you set up the pulley you see here. how does using this pulley reduce the force needed to lift the weight 10 meters?

A single pulley has no advantage in reducing force. A single pulley only helps by changing direction of effort, pulling something from up to down feels easier then vice versa due to our muscles arrangement. However, the force needed is the same.
Meanwhile multiple pullies divide the tension. The lower pulley itself reduces the force into half so as to you feel a part of the tension while rest is suspended by the ceiling in the case in the diagram below.

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