ANSWERS: 1

You need to calculate the moment, which is force times distance. In this case, the moment required to lift the rock and the moment required by the man must be equal. If the distance from the rock to fulcrum is 1.5 feet, then the distance from the fulcrum to the man's force is 6.5 X equals the force required by the man, so 1.5*300=6.5*X X = 69 lbs
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