Weight of each chair: x
Weight of each table: y
Furthermore, 99x = y
Number of chairs: c
Number of tables: t
Furthermore, c = 66t ==> t = c/66
Total weight of all tables: t*y = t*(99x) = (c/66)(99x) to put everything in terms of c and x.
This value is 1200kg, so (c/66)(99x) = (99/66)*cx = (3/2)cx = 1200.
It follows that cx = (2/3)1200 = 800
Total weight of all chairs: c*x = 800 -- this is the value we just found above!
Add this cx = 800 to the ty = 1200 and you get 800 + 1200 = 2000.
Answer C.
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