What always comes into a house through the keyhole?

Count the number of triangles in the given picture.

No matter how little or how much you use me, you change me every month. What am I?

I make a loud sound when I’m changing. When I do change, I get bigger but weigh less. What am I?

Count the Triangle in the figure given below:

A word I know,
Six letters contain,
Subtract just one,
And twelve is what remains.

If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

Using mathematical symbols like +, -, and x in order to make the equations correct. Replace # with the above-given symbols.

9 # 8 # 7 # 6 # 5 # 4 = 91

What's a single-digit number with no value?

What is the word or phrase below?
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