Answer:
Measure the CM from the left end of the canoe
M x = (45 * 1 + 2.5 * 60) M = 105
x = (45 + 150) / 105 = 1.86 m from left end
After she walks 3 m the CM is from the left end
M y = (45 * 4 + 60 * 2.5)
y = (45 * 4 + 60 * 2.5) / 105 = 3.14 m
The left end of the canoe has moved 1.28 m to left
(The CM cannot move without an external force)
Check:
She increases the CM by 45 (3 - 1.28) = 77.4
Canoe movement decreases the CM by 60 * 1.28 = 76.8
1.28 is close