To find the total storage your mobile phone would have after buying the additional bytes, you can add the two amounts:
- The current storage is \(1.28 \times 10^{11}\) bytes.
- The additional storage is \(384,000,000,000\) bytes, which can be expressed in scientific notation as \(3.84 \times 10^{11}\) bytes.
Now, adding these two amounts together:
\[ 1.28 \times 10^{11} + 3.84 \times 10^{11} = (1.28 + 3.84) \times 10^{11} = 5.12 \times 10^{11} \]
Thus, the total storage would be:
\[ \boxed{5.12 \times 10^{11}} \]