How do you go from 98 to 720 using just one letter?

what does the below rebus means?

Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

What word begins and ends with an E, but has only one letter?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

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

A woman is sitting in her hotel room and hears a knock at the door. She opens the door to see a man whom she’s never met before. He says, “I’m sorry, I have made a mistake, I thought this was my room.” He then goes down the corridor and into the elevator. The woman goes back into her room and calls security. What made the woman so suspicious of the man?

How is a fly different from a mosquito?

Why do you find that most of the buildings are deprived of the 13th floor?

The host of a game show offers the guest a choice of three doors. Behind one is an expensive car, but behind the other two are goats.
After you have chosen one door, he reveals one of the other two doors behind which is a goat (he wouldn't reveal a car).

Now he gives you the chance to switch to the other unrevealed door or stay at your initial choice. You will then get what is behind that door.

You cannot hear the goats from behind the doors, or in any way know which door has the prize.

Should you stay, or switch, or doesn't it matter?