Hi eitijan,

This DS question can be solved by TESTing VALUES.

We're asked if G+H > 3.6 This is a YES/NO question.

1) 1.612 < G < 1.718

Fact 1 tells us nothing about the value of H, so it's possible that G+H is greater than 3.6 (a YES answer), but it's also possible that G+H is not greater than 3.6 (a NO answer).
Fact 1 is INSUFFICIENT

2) 1.987 < H < 2.803

Fact 2 tells us nothing about the value of G, so it's possible that G+H is greater than 3.6 (a YES answer), but it's also possible that G+H is not greater than 3.6 (a NO answer).
Fact 2 is INSUFFICIENT

Combined, we know...
1.612 < G < 1.718
1.987 < H < 2.803

IF...
G = 1.6121
H = 1.9871
G+H = 3.5992 and the answer to the question is NO

IF...
G = 1.7
H = 2.8
G+H = 4.5 and the answer to the question is YES
Combined, INSUFFICIENT

Final Answer: E

GMAT assassins aren't born, they're made,
Rich