Can you find out what is missing?

1 3 5
2 4 ?

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

Eight of us go fourth, not back, to protect our king from an attack. What are we?

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?

Can you find the odd number in the following?

2716, 4135, 5321 and 7145

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

In a classic wine shop, the list of three most popular wines are:
- The cost of 1 French wine bottle: 500$
- The cost of 1 German wine bottle: 100$
- The cost of 20 Dutch wine bottles: 100$

John entered the wine shop and he needs to buy
- All three types of wine bottles.
- Needs to buy Dutch wine bottles in multiples of 20.
- Need to buy 100 wine bottles in total.

John has only 10000$. How many wine bottles of each type, John must buy?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

Can you solve this picture maths equation?

What does below pictogram mean?