Percentage Humor

.
Father: How many marks did you get for your math test?

Son: I obtained 100 marks!

Father: Great! You have done me proud. You deserve an ice-cream.

Son: Thanks Dad!

Son to brother: Actually my math test is over a total of 200 marks. I almost failed the test! Luckily dad did not master percentage, otherwise I would not get my free ice-cream.

(To understand percentage, click this link).

..