Answer
$V_{rms} = 64.2~V$
Work Step by Step
In part (c), we found that the $rms$ voltage across $C$ is $159.5~V$
In part (d), we found that the $rms$ voltage across $L$ is $223.7~V$
Note that the potential difference (high potential and low potential) across each of these devices is aligned in opposite directions as we move through the circuit.
We can find the $rms$ voltage across $C$ and $L$ together:
$V_{rms} = 223.7~V-159.5~V = 64.2~V$
