If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

Find The Next Number in this series.
1, 2, 6, 42, 1806 ?

At my favorite fruit stand,
an orange costs 18,
a pineapple costs 27,
and a grape costs 15.
Using the same logic, can you tell how much a mango costs?

A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

What number comes next in the series?

5 15 5 18 5 24 14 20 _

Four children having five rocks each were playing a game in which they had to throw the rock at a particular solid area in the water. Child 1- Succeeded in throwing three rocks at a solid area but one of the rocks sunk. Child 3 - His aim was so bad that all rocks got sunk. Child 4- He was awesome and none of the rocks got sunk. Child 2 - Was the winner but was struck by a rock in the head and died. Who killed Child 2?

If,

A + B = C
D - C = A
E - B = C

Based on the above equations, find out the answer for:

D + F = ?

You have a three-gallon and a five-gallon measuring device. You wish to measure out four gallons.

If you were to put a coin into an empty bottle and then insert a cork into the neck, how could you remove the coin without taking out the cork or breaking the bottle?

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?