The number of rooms on the ground floor of a building is less twice the number of room on the first floor. If the first floor has rooms, how many rooms are there on the ground floor.
The number on first floor are rooms.
Twice the number of rooms on first floor can be written as:
less twice the number of room on the first floor can be written as:
But,
the number of rooms on ground floor is equal to less twice the number of room on the first floor.
Hence the number of rooms on ground floor can be written as: