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

I sleep during the day and fly at night, but I have no feathers to aid my flight. What am I?

John is selling fruits.
He sells grapes at $30, Dates $25, and a Wolfberry $45.
At what price does he sell fig?

PS: Logical Thinking

What is the centre of gravity?

Why did Buffon take the goal with him after every Juventus match?

If Rajina's daughter is my daughter's mom, who am I to Rajina?

Place a mathematical symbol between the numerals 5 and 9 in such a way that the resulting number is greater than 5 but smaller than 9.

How many triangles can you count in the figure given?

Can you solve the tricky chess rebus puzzle below by ciphering the hidden meaning?

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