I have four wings but can't fly.
I express no emotions.
I am found on the exact spot every time you look.
I keep toiling away with a little sound.

Do you know what am I?

The person who makes it has no need for it. He who purchases it does not use it. The person who does use it does not know they are. What is it?

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?

In the city of Brain Teasers, 5% of people do not list their phone numbers. Now if we select random 100 people from the phone directory, then how many people selected will have unlisted phone numbers?

Find the next number in the series.
1 10 24 43 67 ?

What is black when you buy it, red when you use it, and gray when you throw it away?

Before the start of the car race, John and Jacob have the same amount of fuel in their car. With this fuel, John can drive for 4 hours while Jacob can drive five hours.
After a time they realize that the amount of fuel left in John's car is 1/4th of the fuel in Jacob's.

For how long they are racing?

Why Wine Glass Stem is so long?

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

Why do we preferably have round manhole covers and not square ones?