If 21x = 79x, what is the value of x?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

Jenifer and Jesica are having a conversation.

Jenifer: I am definitely not over 30.
Jesica: I am 28 and you are surely 5 years older to me at least.
Jenifer: No, you are at least 29.

You are told that both of them are lying throughout in the conversation. Can you find their respective ages?

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

I am sometimes honest
Sometimes dishonest
I can be sweet and also bitter
I can hurt you real bad and
also make u smile and blush ☺️
What am I?

How many triangles can you find in this given picture?

Use the numbers 2, 3, 4 and 5 and the symbols + and = to make a true equation. Conditions: Each must be used exactly once and no other numbers or symbols can be used.

Before Mount Everest was discovered, what was the highest mountain in the world?

A father's child, a mother's child, yet no one's son.

Who am I?

Cristina was born in 1888. She just had her 30th birthday today how did that happen?