Can you count the number of quadrilaterals in the picture below?

There are three boxes of different sizes with three cupcakes inside each of the boxes in Christina's kitchen. At night her daughter wakes up and goes to the kitchen. She opens a box and eats all three cakes.

But in the morning Christina finds out that each box still had three cupcakes. How?

Different lights make me strange by changing me into different sizes. What am I?

If you read clockwise, you can form a word by inserting three missing letters in the picture given below. Can you do it?

Buy me, smell me or deliver me, I do not change.

Who am I?

There is a brick of gold and a brick of iron in a boat (both 10-inch blocks), if they are both dropped into the water which will make the water level higher?

A beggar on the street can make one cigarette out of every 6 cigarette butts he finds. After one whole day of searching and checking public ashtrays the beggar finds a total of 72 cigarette butts. How many cigarettes can he make and smoke from the butts he found?

In a university, a professor gave a set of three problems to the three brilliant students of his class. See the image for the questions.

Can you find the 09 errors in the picture below?

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?