c) \( \frac{2}{5}+3\left(\frac{1}{2}-\frac{7}{30}\right) \)

To solve the expression \( \frac{2}{5} + 3\left(\frac{1}{2} - \frac{7}{30}\right) \), we first address the parentheses. We need a common denominator to subtract \( \frac{1}{2} - \frac{7}{30} \). The least common multiple of 2 and 30 is 30. Rewriting \( \frac{1}{2} \) with a denominator of 30 gives us \( \frac{15}{30} \). Now we can subtract: \[ \frac{1}{2} - \frac{7}{30} = \frac{15}{30} - \frac{7}{30} = \frac{8}{30} = \frac{4}{15} \] Now we continue with the original expression: \[ \frac{2}{5} + 3\left(\frac{4}{15}\right) = \frac{2}{5} + \frac{12}{15} \] Next, we convert \( \frac{2}{5} \) to have a common denominator with \( \frac{12}{15} \). We can convert \( \frac{2}{5} \) to \( \frac{6}{15} \) (since \( 2 \times 3 = 6 \) and \( 5 \times 3 = 15 \)). Now, we can add: \[ \frac{6}{15} + \frac{12}{15} = \frac{18}{15} \] Finally, we simplify \( \frac{18}{15} \) to \( \frac{6}{5} \) or \( 1.2 \). Thus, the final answer is: \[ \frac{6}{5} \text{ or } 1.2 \]