Statement 1 gives the value of G of which we are not concerned. Not sufficient.
Statement 2 gives a just relation between G and F. Not sufficient.
Now on combining we merely get to know that frequency of F is 19kHz.
Given fact is: Frequencies greater than or equal to 22 kHz are inaudible to the human ear. BUT it doesn't tells us the exact value beyond which the inaudibility starts.
consider the example: integers less than or equal to -5 are negative. But does really the negative numbers start from -5? No. We need the exact value beyond which the negative range starts to say even something.
The same principle applies here.
Hope that helps.
Prepositional Phrases Clarified|Elimination of BEING| Absolute Phrases Clarified
Rules For Posting