You and your little cousin sit on a see-saw. You sit 0.39 m from the fulcrum, and your cousin sits 1.53 m from the fulcrum. You weigh 620 N. How much does she weigh?

620 * .39 = x * 1.53

so

(.39/1.53)620

To find out how much your cousin weighs, we can use the principle of torque. The torque is equal to the weight multiplied by the distance from the fulcrum.

The torque on your side is given by:
Torque1 = Weight1 × Distance1

The torque on your cousin's side is given by:
Torque2 = Weight2 × Distance2

Since the see-saw is in equilibrium (balanced), the total torque on both sides is equal. Therefore, we can set up the equation:

Torque1 = Torque2

Weight1 × Distance1 = Weight2 × Distance2

We can substitute the given values into the equation:
620 N × 0.39 m = Weight2 × 1.53 m

Now, let's solve for Weight2:
Weight2 = (620 N × 0.39 m) / 1.53 m

Weight2 = 159.870 N

Therefore, your cousin weighs approximately 159.870 Newtons.