A building contains 20 rooms in total. 9 of the rooms are on the ground floor.
7 of the rooms have white walls.
2 of the rooms that are on the ground floor also
have white walls.
Work out the probability that a room picked at
random is neither on the ground floor nor has white
walls.
Give your answer as a fraction in its simplest form.

Does the construction demonstrate how to copy an angle correctly using technology a) yes the distance between points a and f was used to create circle h b) yes the distance between points f and g was used to create circle h c) no the distance between points a and f was used to create circle h d) no the distance between points f and g was used to create circle h