What goes up but never comes down?

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

In the below-given picture of a pretty girl, there is something wrong. Can you find out what it is?

I know a 5-digit number having a property that With a 1 after it, it is three times as large as it would be with a one before it.

Guess the number?

What can you deduce from the following BrainBat?

CRY
LMKI

Count the squares in the matchstick puzzle below?

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

By removing one matchstick and adding one matchstick, can you convert the word "ZOO" to an animal name?

A Shopkeeper collects 71 rupees in the form of 20 paisa and 25 paisa.
He collects a total of 324 coins.

Can you tell me how many number of 20-paisa and 25-paisa he got?

Make eight squares by moving only two matchsticks.
Note- Square can be of different sizes.