Can you circle exactly four of these numbers such that the total is twelve?

1 6 1
6 1 6
1 6 1
6 1 6

Below, you will find the mathematical proof that 10 equals 9.99999?. But is that possible or there is something wrong about it? Can you find the error?

x = 9.999999...
10x = 99.999999...
10x - x = 90
9x = 90
x = 10

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

If a zookeeper had 100 pairs of animals in her zoo, and two pairs of babies are born for each one of the original animals, then (sadly) 23 animals don’t survive, how many animals do you have left in total?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

What part of Turkey has the most feathers?

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

What is the end of everything?

What number comes next in the series?

5 15 5 18 5 24 14 20 _

On a beautiful Sunday morning, You ordered a hot tea to your hotel room and suddenly you remember an important thing that needed to be done right now will take around 3 minutes to complete.
Like most people you like your tea to be hot while drinking so, when should you pour cream in the tea?
1. straight away
2. Just people, you drink the team
3. Its does not matter