Why is Saturday stronger than Monday?

Count the number of triangles in the below picture?

When my father was 31 I was 8. Now he is twice as old as me. How old am I?

It has a long neck, A name of a bird, Feeds on cargo of ships, It's not alive,

What is it?

Can you find a number that lies one third of the distance between 1/3 and 2/3?

What are the 50th, 63rd and 100th numbers in the sequence below?
4, 5, 8, 8, 9, 9, 12, 13, 13, 13, 17, 18, ...

What is the centre of gravity?

A man lives on the fifteenth floor of an apartment building. Every morning he takes the elevator down to the lobby and leaves the building. In the evening, he gets into the elevator, and, if there is someone else in the elevator, or if it was raining that day, he goes back to his floor directly. Otherwise, he goes to the tenth floor and walks up five flights of stairs to his apartment. Can you explain why he does this?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

A deaf and mute man goes to the train station. Tickets for the train are 50 cents each. The man goes to the ticket booth and hands the man inside just a dollar. The man in the booth hands him two tickets.

How did the man in the booth know to give him two tickets without even looking at him?