If the average (arithmetic mean) of the assessed values
of x houses is $212,000 and the average of the assessed
values of y other houses is $194,000, what is the average
of the assessed values of the x+y houses?
(1) x+y=36
(2) x=2y

The way I solved it.
Total cost of the x houses = 212000x
Total cost of the y houses = 194000y
So the average of the assessed values of the x+y houses is

(212000x + 194000y)/(x+y) .......(1)

Statement 1 : Not Sufficient as it only gives the value of x+y=36
Statement 2 : In my opinion Sufficient

(212000(2y) + 194000(y))/(2y+y)
(212000(2y) + 194000(y))/(3y)
618000y/3y = 206000
Hence the answer is B.

However the QA is given a C.