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## Homework Statement

Two people, one of mass 75kg and the other of mass 60kg, sit in a rowboat of mass 80kg. With the boat initially at rest, the two people, who have been sitting at opposite ends of the boat, 3.2m apart from each other, exchange seats.

How far will the boat move?

and in what direction will the boat move?

## Homework Equations

xcm=x1m1+x2m2+xbmb/(m1+m2+mb)

## The Attempt at a Solution

m1=75kg person initially on left end of boat.

m2=60kg person initially on right end of boat.

mb=80kg boat

my origin is at the left end of the boat and the 75kg person is initially there.

xcm=x1m1+x2m2+xbmb/(m1+m2+mb)

xcm=(0)(75kg) + (3.2)(60kg) + (1.6)(80kg)/(75kg+60kg+80kg)

xcm= 1.4883m

Now for my final(center of mass doesn't move)

1.4883m=x1m1+ x2m2 +xbmb/(m1+m2+mb)

1.4883m= (3.2m)(75kg) + (0)(60kg) + xb(80kg)/(215kg)

xb(final) = 1.004375m

xb(final)-xb(initial)

1.004375m- 1.4883m=-.4839m

Is this correct? Thanks!