Rule of three

If it takes four men one day to build a wall, how long does it take 60,000 men to build a similar wall?
Exploring and noticing Working systematically Conjecturing and generalising Visualising and representing Reasoning, convincing and proving
Being curious Being resourceful Being resilient Being collaborative

Problem

"I quite agree with you," said the Duchess, " and the moral of that is - 'Be what you would seem to be' - or, if you'd like it put more simply - 'Never imagine yourself not to be otherwise than what it might appear to others that what you were or might have been was not otherwise than what you had been would have appeared to them to be otherwise."

If it takes $4$ men one day to build a wall, how long does it take $60$ $000$ men to build a similar wall?