what does the below math rebus puzzle mean?

Can you find out the missing number in the grid?

John enters a small room. The Door Closes.
When the door opens, John is in a larger room.

Explain?

Can you solve the equation by finding the value of
A) Horse
B) Cowboy boot
C) Horseshoe

In the Picture?

In a certain country ½ of 5 = 3. If the same proportion holds, what is the value of 1/3 of 10?

I have a big mouth and I am also quite loud! I am NOT a gossip but I do get involved with everyone's dirty business.

There is a bag which have 21 blue balls and 23 red balls. You also have 22 red balls outside the bag. Randomly remove two balls from the bag. * If they are of different colors, put the blue one back in the bag. * If they are the same colour, take them out and put a red ball back in the bag. Repeat this until only one ball remains in the bag. What is the color of the sole ball left in the bag ?

A 3 digit number is such that it's unit digit is equal to the product of the other two digits which are prime. Also, the difference between it's reverse and itself is 396.

What is the sum of the three digits?

I know a 5-digit number having a property that With a 1 after it, it is three times as large as it would be with a one before it.

Guess the number?

No one wants to have it, but if one got it, he does not want to lose it. What is It?