Why do people go to bed?

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

I know a ten-letter word in the English language which can be typed using only the top rows of the computer keyboard.

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

I know a nine-letter word having only one vowel.
Do you ?

What kind of tree can you carry in your hand?

In a contest, four fruits (an apple, a banana, an orange, and a pear) have been placed in four closed boxes (one fruit per box). People may guess which fruit is in which box. 123 people participate in the contest. When the boxes are opened, it turns out that 43 people have guessed none of the fruits correctly, 39 people have guessed one fruit correctly, and 31 people have guessed two fruits correctly.
How many people have guessed three fruits correctly, and how many people have guessed four fruits correctly

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?

It has horns but can’t beep. It is like to bleat but It is not a sheep. What is it?

A boy collects white seashells from the sea and brings them home every night. When he has enough of them, he decides to sell them to a trader.

The trader is ready to buy the shells and he asks the boy about the quantity. At this, the boy starts calculating. He has a giant box that contains 3 mini boxes. Two of them have another mini box inside. If the giant box can hold 50 shells, how many brown shells can he sell to the trader?