Question

two cats are sitting on a seesaw which is a 3-metre long wooden plank weighing 2kg. the cat on the right is 0.5m from the pivot point and has a mass of 12kg. The cat on the left is 1.3m from the left and of the plank as shown in the figure. Calculate the mass of the cat sitting on the left side if the plank remains horizontal.

Answer 1

I guess the pivot point is at the center, 1.5 from left?
if so
cat on left is 1.5 -1.3 = .2 from pivot
cat on right is at .5 from pivot
plank weight is at pivot
so
m * .2 = 12*.5
m = 6/.2 = 30 kg

Answer 2

d1 = 0.5 m.
M1 = 12kg.

d2 = 1.5 - 1.3 = = 0.2 m.
M2 = ?

M1*d1 = M2*d2.
12 * 0.5 = M2 * 0.2,
M2 = ?

m