Refer to figure.
Use the acronym C-D-M-V-T, and replace the values you are given in the question:
242° – D – M – 22°E – T

You are also given a deviation table that will allow you to find the magnetic heading. You’re currently maintaining a compass heading of 242°, therefore you look for this value in the lower line of the deviation table. The value above 242°, in the ‘to fly’ line is 240°.
This means that while maintaining a compass indication of 242°, you are flying in reality on a magnetic heading of 240°.

Our acronym becomes now as follows:
242° - D – 240° - 22°E - T

You don’t really need to find the deviation because you already have the magnetic heading and the variation.

Thanks to the acronym CADET you can easily find the true heading of the aircraft. Moving from the left to the right of the acronym, you need to add if the variation is East (CADET = AD (add) E (east)). In our case, the variation is East, therefore you need to add the 22°E variation to the magnetic heading to obtain a True heading of 262°.

It is not needed, nor asked in this question to find the deviation. But you can do it anyway to exercise the two acronyms and get better at solving this type of question.
Thanks to the acronym CADET you can easily deduce that the variation is 2°W. In fact, in the direction from C (compass) to T (true) you need to add the deviation whenever it is E (east). In our case we initially have a value of 242° and moving to the right of the acronym (towards T=true), you obtain a value of 240° magnetic heading - the difference hasn’t been added but subtracted. Therefore, the deviation is West.