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

A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

What number comes next in the series?

5 15 5 18 5 24 14 20 _

Forwards I am heavy, backward I am not. What am I?

What can go through glass without breaking it?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

Complete the table series riddle by finding the number that can replace "??".

You see me once in June, twice in November, and not at all in May. What am I?

Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

I am a white box having no key or lid.
Yet there is a golden treasure inside it.

What Am I?