25771

Each table has 3 legs, each table has 4 chairs with it. Each chair has 4 legs and there are 3 people at each table, because only 3/4 of all the chairs are taken.

So 3 + 4x4 + 3x2 =25
25 is the number of legs at each table.

206 legs - 6 legs of the members of staff = 200 legs

200 / 25 = 8
So there are 8 tables. There are 4 chairs at each table. 8 x 4 =32
So there are 32 chairs altogether