What does this rebus means ?

PROG WORKRESS

What work can one never finish?

A prisoner is told: "If you tell a lie, we will hang you and if you tell the truth, we will shoot you." What did the prisoner say to save himself?

Why is a river so rich ?

When can we add 2 to 11 and get 1 as the correct answer?

John and Jenni are a married couple. They have two kids, one of them is a girl. Assume safely that the probability of each gender is 1/2.
What is the probability that the other kid is also a girl?

Hint: It is not 1/2 as you would first think.

What is the Surname of Barbie Doll?

If eleven plus two equals one, what does nine plus five equal?

There’s a girl who has a large family. She has an equal amount of brothers and sisters, but each brother only has half as many brothers and sisters. What’s the correct amount of brothers and sisters?

Prove that twice of ten is the same as twice of eleven.