Determining Juliet's Weight Using Center of Mass Principle

[stanford1463]

Homework Statement

The question is: Romeo and Juliet are dating on a canoe in a lake. They are 4 feet apart, and Romeo wants to see how much Juliet weighs. He is on the left, Juliet on the right. So, he decides to switch spots with her. After switching, the boat moves 0.444 feet to the left. Romeo weighs 160 pounds. How much does Juliet weigh?

Homework Equations

Center of mass= sum (mgx) /sum (mg)

The Attempt at a Solution

Since the center of mass remains the same, the center of mass of the initial position is equal to the center of mass of the final position, minus 0.444 (since it moved to the left 0.444 feet). After solving for x ( weight of Juliet), I got 142 pounds..is this right? Please help..it sounds right, since Romeo weighs 160 pounds, and the boat moved to the left 0.444 feet (due to friction, and romeo is heavier...) thanks!

 

[stanford1463]

bump...please? any help?

 

[stanford1463]

Edit: I actually got 128 pounds, (little algebraic mistake). So, Juliet weights 128 pounds, is this correct..? Thanks!