Which cup will be filled first?
What you need to answer this
1. Attention to detail
2. Scientific reasoning
Solution:
Clue: Use logic to identify the cups which wont get filled.
One of the most common answers is that it’s impossible to say what cup will be filled first, as you need to know the flow rate to answer the question.
For example, if Cup 7 drains faster than water pours from the spout, then Cup 7 will never be filled.
But people who say this are missing a few important things..
People tend to look for the lowest tunnels to see where the water will drain first. Using this logic, the most obvious answer is Cup 4, as the lowest tunnels point to that cup.
However, if you look closely, you will see that the tunnel to Cup 4 is blocked off, so the water can’t fill cup 4. There’s also a block just before Cup 5 and Cup 6, so those cups also can’t be filled.
There is a hole at the bottom of Cup 7, which is what Cup 2 drains into. But here’s the thing — the flow rate doesn’t matter, as Cup 3 will start filling before Cup 2 or 7. And Cup 2 won’s start filling until Cup 3 is totally full.
Cup 3 will be filled first