Can you convert the number zero(0) into a positive number using just one mathematical operator ?

There are forty elephants and they have forty-fore heads. How can this be possible?

Find out the missing number in the picture attached:

Four men were in a boat on the lake. The boat turns over, and all four men sink to the bottom of the lake, yet not a single man got wet! Why?

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

People make me, save me, change me, raise me. What am I?

There’s a girl who has a large family. She has an equal amount of brothers and sisters, but each brother only has half as many brothers and sisters. What’s the correct amount of brothers and sisters?

I can turn polar bears white.
I can make anyone dance.
I can make everyone cry
I can make your hands clap
I can make you thin.
I can make you smile.
I can make you smile

Can you guess the riddle?

It's a 7-letter word.
If we remove 1 letter from it, it remains the same.
If we remove 2 letters from it, it remains the same.
If we remove 3 letters from it, it remains the same.
If we remove all the letters from it, still it remains the same.
What is it?

What 5-letter word typed in all capital letters can be read the same upside down?