In a concert, Christina is performing a dance show with her group.
At 10:00, she and her crew were dancing in an absolutely straight line. At that time Christina was standing in 4th position from both the front and back end of the row.

What was the size of her crew?

There is a shop where written:
Buy 1 for $1
10 for $2
100 for $3
I needed 999 and still only paid $3. How could this be financially viable for the shop-keeper?

There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?

Is the statement valid that it does not matter how much older a sibling is, eventually the younger one will be half as old as the older one?

Replace the question mark with the number below given a simple math problem.

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

An ant is travelling on a 1-meter-long rope at 1 cm/second but also the entire rope is being stretched by an extra 1 meter/second. Is it possible for the ant to reach at the end of the rope?

Okay before we begin with the puzzle, do keep in mind that you have to answer it quickly.

You are participating in a car race. Seeking the perfect moment, you overtake the second person in the race. What positions are you in now?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

Find the next number in the series

12, 20, 40, 72, 116, 172 ?