In what year was Professor Slughorn Head of Slytherin House? (Hint: Think Potions Class)

What number is on the Hogwarts Express platform?

How many points did Gryffindor win by to win the house cup during Harry's first year?

What is the exact number of staircases in Hogwarts castle?

What is the price of a ticket on the Knight Bus, if you also want hot chocolate?

What is the number of the vault where the Philosopher's Stone was hidden?

In Harry's 3rd year, How many sickles did Ron have in his pocket?

What is the total combined age of the three founders of Hogwarts who aren't Salazar Slytherin (in years)? Assume they all died in 1000 AD when the school was founded.

How many Weasley children are there?

Approximately how many students attended Hogwarts?