I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

Which is the smallest number that you can write using all the vowels exactly once?

Can you find the next number in the below sequence
3 , 7 , 10 , 11 , 12 , 17 ?

I am the largest in my family of fifty.
The youngest of our family lives separately from the rest of the family and so do I.
I am regarded as harsh and tough.
I am so large, you cut me in two equal halves,
each half would still be larger than the second largest member of the family.
Who am I?

A kind heart person buy packed food at 3$/packet from United states and sells them at 1$/packet at Africa. After some time he becomes a millionaire.

How come the guy become millionaire ?

Can you find the odd number in the following?

2716, 4135, 5321 and 7145

Why do people go to bed?

At a party, there are five people and a whole round cake lying at the centre of the table. Only four people will make a cut and take their piece and the last one will get the remaining piece on the table. How can they make sure that everyone gets a 1/5th of the piece?

A man started to town with a fox, a goose, and a sack of corn. He came to a stream which he had to cross in a tiny boat. He could only take one across at a time. He could not leave the fox alone with the goose or the goose alone with the corn. How did he get them all safely over the stream?

What does it mean?