To divide \(4\) by \(\frac{3}{10}\), you can multiply \(4\) by the reciprocal of \(\frac{3}{10}\).
The reciprocal of \(\frac{3}{10}\) is \(\frac{10}{3}\).
Now, perform the multiplication:
\[ 4 \div \frac{3}{10} = 4 \times \frac{10}{3} \]
Multiply:
\[ 4 \times \frac{10}{3} = \frac{40}{3} \]
So, \(4 \div \frac{3}{10} = \frac{40}{3}\), which can also be expressed as a mixed number:
\(\frac{40}{3} = 13 \frac{1}{3}\).
Thus, the answer is:
\[ \frac{40}{3} \text{ or } 13 \frac{1}{3} \]