What do you get if you add 2 to 100 four times?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

A doctor and a boy were fishing. The boy was the doctor’s son, but the doctor was not the boy’s father. Who was the doctor?

What two things can you never eat for breakfast?

Why do we preferably have round manhole covers and not square ones?

A frog is at the bottom of a 30-meter well. Each day he summons enough energy for one 3-meter leap up the well. Exhausted, he then hangs there for the rest of the day. At night, while he is asleep, he slips 2 meters backwards. How many days does it take him to escape from the well?

Which tank will fill first?

What number comes next in this sequence:
7 8 5 5 3 4 4 _

You have four chains. Each chain has three links in it. Although it is difficult to cut the links, you wish to make a single loop with all 12 links. What is the fewest number of cuts you must make to accomplish this task?

1 + 9 + 8 = ?
considering, 28 + 8 + 92 = 10