A train leaves from point A for point B at 80 mph. After half an hour, another train leaves from point B for point A at 60 mph.

Which of the trains will be farther from point A when they meet ?

Can you find out what is missing?

1 3 5
2 4 ?

Hint: It's not six. Think out of the box.

Here is a mathematical expression that also secretly tells a movie name. What movie is that?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

I am a type of room you cannot enter or leave. Raised from the ground below, I could be poisonous or a delicious treat. What am I?

A thief enters a store and threatens the clerk, forcing her to open the safe. The clerk says, “The code for the safe is different every day, and if you hurt me you’ll never get the code.” But the thief manages to guess the code on his own. How did he do it?

Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

I am the beginning of the end, and the end of time and space. I am essential to creation, and I surround every place. What am I?

Can you find the least possible number such that

If the number is divided by 3, it gives the remainder of 1;
If the number is divided by 4, it gives the remainder of 2;
If the number is divided by 5, it gives the remainder of 3;
If the number is divided by 6, it gives the remainder of 4.

As shown in the image, the nine Dogs are square fenced. By constructing just two square fences can you make sure that two Dogs cannot meet each other without crossing the fence?