The Captive Queen
A Classic Puzzle by Lewis Carroll
A captive queen and her son and daughter were shut up in the top room of a very high tower. Outside their window was a pulley with a rope around it, and a basket fastened to each end of the rope of equal weight. They managed to escape with the help of this and a weight they found in the room, quite safely. It would have been dangerous for any of them to come down if they weighed 15 lbs more than the content of the other basket, for they would do so too quick, and they also managed not to weigh less either.
The one basket coming down would naturally of course draw the other basket up.
The queen weighed 195 lbs, daughter 105, son 90, and the weight 75 lbs.
How did they all escape safely?