Answer:
3
Step-by-step explanation:
Using the efficiency formula. Efficiency = MA/VR * 100%
MA = Mechanical Advantage
VR = velocity ratio =

Distance moved by effort = 4.5m
distance moved by load = 1.5m
VR = 4.5/1.5 =3
Assuming efficiency is 100% (since friction can be ignored)
100% = MA/3 * 100%
1 = MA/3
MA = 3*1
MA = 3
Mechanical Advantage of the ramp is 3