Question

Two children weighing 40 lbs and 50 lbs each are balancing their teacher weighing 120 lbs on a seesaw. The teacher is sitting 5 feet from the fulcrum, and the child weighing 50 lbs is seated 8 feet from the fulcrum. Find the distance (in feet) from the fulcrum where the child weighing 40 lbs should taker her place.

Answer 1

Answer:

5 feet

Explanation:

First lets imagine that the values are in meters and kg, to make it easier for me.

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The force created by the teacher is 120 × 5 = 600N.

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The force created by the 50 kg student is 50 × 8 = 400N

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The force that needs to be created by the 40 kg student is 600N - 400N = 200N.

To create that force that student needs to sit 200 ÷ 40 = 5m.

So the 40 lbs student is sitting 5 feet from the fulcrum.