Difficulty: Extreme!
In two hours from now, it will be half as many hours until noon as it would be if it was just one hour from now.
What’s the time right now?
Need a hint?
Try ‘waiting’ an hour and rephrasing the problem: In one hour, it’ll be half as many hours to noon as it is now.
Now try waiting another hour. What will the question say now?
Brainteaser answer
The answer is 9am. You can check because just one hour from then, at 10am, it would take two hours to get to noon. Meanwhile two hours from 9am, at 11am, it would take half as many hours – one hour – to get to noon, just as the problem says.
This problem is written to be a bit confusing, with important times all happening in the future.
The two important times happen 1 hour and 2 hours in the future. Let’s imagine we just wait for an hour and see if that makes things easier.
The problem should now say:
In one hour, it’ll be half as many hours to noon as it is now.
This problem is still tricky, but we can solve it with waiting too. Waiting another hour will halve the time to noon, so waiting 2 more hours will get us to noon!
To answer the original question, we need to remember to add up all the time we waited to get to noon. The first hour, and then 2 more hours, making three hours.
So if we started 3 hours before noon, it must be 9 AM!