Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

What is the Surname of Barbie Doll?

You want to boil a two-minute egg. If you only have a three-minute timer (hourglass), a four-minute timer and a five-minute timer, how can you boil the egg for only two minutes?

Can you find out the smallest number that can be conveyed as the sum of three squares in three unique ways?

A cat, a dog and a monkey were stolen. 3 suspects got caught: Harish, Manoj and Tarun. All we know is each person stole one animal, but we do not know who stole which. Here are the investigation statements. Harish said: Tarun stole the cat. Manoj said: Tarun stole the dog. Tarun said: They both were lying. I did not steal the cat or the dog. Later on, the police found out the man who stole the monkey told a lie. The man who stole the cat told the truth. Can you find out who stole which?

What does this mean?

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How many triangles are there in the picture below?

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

There are three houses in a straight row. One is red, one is blue, and one is white. The red house is left of the middle. The blue house is right of the middle. Where's the white house?

What always comes into a house through the keyhole?