You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

At my favorite fruit stand,
an orange costs 18,
a pineapple costs 27,
and a grape costs 15.
Using the same logic, can you tell how much a mango costs?

I am white when I am dirty, and black when I am clean. What am I?

A cricket has 6 legs, a squirrel has 4 legs and a spider has 8 legs.

In a local zoo, it was found that the total number of legs is 612. Also, there are equal number of each of the above animals/insects.

Can you find out how many animals are there in the zoo?

People make me, save me, change me, raise me. What am I?

Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

How many times can you subtract the number two from the number fifty?

What can go up a chimney down, but can’t go down a chimney up?

How many bricks does it take to complete a building that is 15 feet wide, 30 feet deep, and 12 feet tall made of brick?

What is so fragile that saying its name breaks it?