When can we add 2 to 11 and get 1 as the correct answer?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

How many triangles can you find in this given picture?

What has hands, but can’t clap?

Replace the question mark with the correct number.

One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

A man says, "Brothers and sisters, have I none, but that man's father is my father's son." Who is that man?

There are 100 bulbs in a room. 100 strangers have been accumulated in the adjacent room. The first one goes and lights up every bulb. The second one goes and switches off all the even-numbered bulbs - second, fourth, sixth... and so on. The third one goes and reverses the current position of every third bulb (third, sixth, ninth? and so on.) i.e. if the bulb is lit, he switches it off and if the bulb is off, he switches it on. All the 100 strangers progress similarly.

After the last person has done what he wanted, which bulbs will be lit and which ones will be switched off?

A non-stop marathon is the shared favourite sport of three brothers.

*The oldest one is fat and short and trudges slowly on.
*The middle brother's tall and slim and keeps a steady pace.
*The youngest runs just like the wind, speeding through the race.

"He is young in years, we let him run!" the other two brothers explained, "'because though he is surely number one, he is second, in a way." Why is it?

Count the number of lines in the image below ?