When I get multiplied by any number, the sum of the figures in the product is always me. What am I?

If two's company, and three's a crowd, then whats four and five ?

Can you find the largest Three-digit number whose sum is 14 and whose square is less than 5,00,000?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

A woman named Maria was at the funeral of her mother. She met a nice young man that she had never seen before and after the service, they spent a bit of time together. Then she got busy and didn’t get his name or phone number before he left. She tried to find him, but no one knew who he was or how to contact him. A few weeks later, Maria’s older sister dies and the police suspect murder. Who killed the sister?

A train leaves from point A for point B at 80 mph. After half an hour, another train leaves from point B for point A at 60 mph.

Which of the trains will be farther from point A when they meet ?

A boy and a girl are sitting on the porch.
"I'm a boy," says the child with black hair.
"I'm a girl," says the child with red hair.
If at least one of them is lying, who is which?

By removing one matchstick and adding one matchstick, can you convert the word "ZOO" to an animal name?

Can anyone tell me a word in the English dictionary which has a silent 'z'?

Nine marbles are arranged in the image below. Can you slide two marbles to form a square?