How many words can a pen with half refill write?

I always drive my customer away.

Who am I?

Can you make four (4) nines (9) equal 100?

You need to move three matchsticks to form three squares. Can you do it?

John drives to his office at 20km/hr. After reaching the office, he realizes that today is a holiday. He went back at an average speed of 30km/hr. Discounting the time spent in the stoppage what was the average speed of his journey?

How much will a 38° angle measure when looked at under a microscope that magnifies ten times?

Can you find the ages of a son, father and grandfather based on the following facts?
The sum of the ages of grandfather, father and son is 140 years.
The age of the son in months is the same as the grandfather in years.
The age of the son in days is the same as the father in weeks.

Why is the Hole below a Lock?

Which number should replace the question mark?

I have no life, but I can die. What am I?