Today's puzzle

P 27
Another puzzle from Henry Earnest Dudeney !


A rope is passed over a pulley. There’s a rope at one end and a monkey at the other. On both sides, the length of the rope is the same. The rope weighs 4 ounces per foot. The total age of the monkey and its mother is 4 years. The monkey weighs as many kg as its mother is years old. The monkey’s mother is twice as old as the monkey was when the monkey’s mother was half as old as the monkey will be when the monkey is three times as old as the monkey’s mother was when the monkey’s mother was three times as old as the monkey. The weight of the rope and the weight at the end was half as much again as the difference in weight between the weight of the weight and the weight and the weight of the monkey.
What was the length of the rope ?