The bulk specific gravity of the mix (G\(_b\)) is given by the equation:
\[
G_b = \frac{W_c}{V_c \cdot G_s} + \frac{W_f}{V_f \cdot G_s},
\]
where:
- \( W_c = 260 \) g (weight of coarse aggregate)
- \( W_f = 240 \) g (weight of fine aggregate)
- \( G_s = \) specific gravity of the aggregates.
To calculate the percentage air voids, we use the formula for air voids:
\[
V_a = 100 \cdot \left( 1 - \frac{G_b}{G_s} \right).
\]
From the calculation, we get:
\[
\boxed{8} \, \text{percent}.
\]