here got E
but have trouble in transforming 2 st into math terms. hope that it is x>1.2y

is x>65/100(y+z), is 100x>65(y+z), is 20x>13(y+z)
(1) insufficient as z is not mentioned, but given that x>1.2y

(2)z/y=45/52. z=(45/52)y
y+z=y+(45/52)y=(97/52)y. 13*(97/52)=97/4=24,25 and is 20*x>24.25y again insuff as relation between x and y is not given
together
if x>1,2y, then for simplicity x=1.2y 20*1.2=24 a little bit more that 24, but can be more that 24,25 or less that 24, 25 insufficient

Hi all!
IMO E
x > 0.65(y + z)
(1) x > 1.2y
We don't know anything about z.
Statement (1) ALONE is INSUFFICIENT
We should eliminate answer choices A & D.
(2) z/y = 45/52
x > 0.65(y + 45/52y)
x > 0.65* 97/52y
x > 65*97/5200y
x > 6305/5200y
Statement (2) ALONE is INSUFFICIENT
We should eliminate answer choice B.
(1) & (2)
If x > 1.2y, is x > 6305/5200y?
x > 1.2*5200/5200y
x > 6240/5200y
Statements (1) & (2) both are together INSUFFICIENT
We should eliminate answer choice C and choose answer E.

Hope it helps!
Best,
Maciek

OA is E indeed