I’m tall when I’m young, and I’m short when I’m old. What am I?

When my father was 31 I was 8. Now he is twice as old as me. How old am I?

Count The number of F's in the paragraph below:

"FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS"

One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

What has many keys but can’t open a single lock?

Joseph buys three kinds of chocolates for 100 rupees. The first one is priced at 5 rupees, second one at 3 rupees and third one at 0.5 rupees.

If he bought 100 chocolates in total, how many pieces do you think he bought each chocolate?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

What is full of holes but still holds water?

A woman shoots her husband.

Then she holds him under water for over 5 minutes.

Finally, she hangs him.

But 5 minutes later they both go out together and enjoy a wonderful dinner together.

How can this be?

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?