A playground merry-go-round of radius r = 1.82m has a moment of inertia of i = 221kgm2 and is rotating at 14.8rev/min about a frictionless vertical axle. Facing the axle, a 22.4kg child hops onto the merry-go-round and manages to sit down on its edge. What is the new angular speed (in revolutions per minute) of the merry-go-round?
a) 13.7
b) 15.3
c) 16.9
d) 18.2