Answer
The fraction of the volume of the iceberg that would be visible is $~~0.083$
Work Step by Step
We can find an expression for the mass of the iceberg:
$m = \rho_i~V_i$
This mass of water is displaced by the iceberg. We can find the volume of water that is displaced:
$V_w = \frac{m}{\rho_w}$
$V_w = \frac{\rho_i~V_i}{\rho_w}$
We can find the ratio $\frac{V_w}{V_i}$:
$V_w = \frac{\rho_i~V_i}{\rho_w}$
$\frac{V_w}{V_i} = \frac{\rho_i}{\rho_w}$
$\frac{V_w}{V_i} = \frac{917~kg/m^3}{1000~kg/m^3}$
$\frac{V_w}{V_i} = 0.917$
Then the fraction of the volume of the iceberg that would be visible is $~~1-0.917~~$ which is $~~0.083$
