John was working on a Chemical Mixture whose weight comprise 90% liquid and 10% solid. The total weight of the mixture is 20 pounds. After a while, John noticed that some of the liquid evaporated and now the liquid comprises just 50% of the weight.

What is the weight of the chemical mixture now?

It is Secret Agent Bond Girl Friend's birthday but he is on a secret mission

Mr Bond has a secret device by which he can only use the below words for sending the message.

Dumbo, Nazi, Carrot, Ronda, Zambia, Racing, TinTin, Seou, Zareeba, Laltain, Saphire, Tar, Orphan, Audition, Biscotti.

Mr Bond sends the following message to her girlfriend:
Carrot Dumbo Nazi Racing Ronda Zambia TinTin Seou Laltain Zareeba Tar Biscotti Orphan Audition Snake

What does Mr. Bond's Message say?

The host of a game show, offers the guest a choice of three doors. Behind one is a expensive car, but behind the other two are goats.
After you have chosen one door, he reveals one of the other two doors behind which is a goat (he wouldn't reveal a car).

Now he gives you the chance to switch to the other unrevealed door or stay at your initial choice. You will then get what is behind that door.

You cannot hear the goats from behind the doors, or in any way know which door has the prize.

Should you stay, or switch, or doesn't it matter?

In particular commonwealth games, a female participant won silver and gold medals for a single event.

How can this be possible?

I am an odd number. Take away a letter and I become even. What number am I?

You are in a room that has three switches and a closed door. The switches control three light bulbs on the other side of the door. Once you open the door, you may never touch the switches again. How can you definitively tell which switch is connected to each of the light bulbs?

Can you replace the question mark with the correct letter?

6 + 6 + 6 = N
7 + 7 + 7 = E
8 + 8 + 8 = R
0 + 0 + 0 = ?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

I’m tall when I’m young, and I’m short when I’m old. What am I?

These types of puzzles are known as charades. What you have to do is find two words that are referred to in the first stanza and the second stanza and put them together to form the third word in the third stanza.

Just for example, if my first refers to 'off' and my second refers to 'ice', then my whole will be office.

My first is present - future's past -
A time in which your lot is cast.

My second is my first of space
Defining people's present place.

My whole describes a lack of site -
A place without length, breadth, or height.