The exact number of letters was never specified.
She was in Gryffindor House at Hogwarts.
Harry doesn't exactly have a house. . .he lives with his aunt and uncle, but it's not really his house, and he spends the other half of his time in Hogwarts and at the Burrow (Ron's house).
Cho Chang is in the house Ravenclaw in Hogwarts
The house of Helga Hufflepuff at Hogwarts,the house stands for kindness.
at harrys house giving them blowies
That is unknown. She may not even have attended Hogwarts.
Rubeus Hagrid was in Gryffindor at Hogwarts School of Witchcraft and Wizardry. Hagrid was in the Gryffindor house.
Hufflepuff.
Slytherin.
Pansy Parkinson was in Slytherin house.
The house of Godric Gryffindor at Hogwarts,the house stands for bravery.
The house of Rowena Ravenclaw at Hogwarts,the house stands for smarts.