To solve the expression \(\left(\frac{7a}{4}\right)^{3}\), we need to raise the fraction \(\frac{7a}{4}\) to the power of 3. This involves raising both the numerator and the denominator to the power of 3 separately.
Step 1: Evaluate the Expression
We start with the expression \(\left(\frac{7a}{4}\right)^{3}\). To evaluate this, we substitute \(a = 1\):