here is the question: I am confused about the steps I need to follow to be able to complete this question some explanation will be appreciated :)

In a Multiple - choice examination of 25 questions, four marks are
given for each correct answer and two marks are deducted for each
wrong answer. One mark is deducted for any question which is not
attempted.
A candidate attempts q questions and gets c correct.
a) Write down an expression for the candidate's total mark in terms of
q and c.
b) James attempts 22 questions and scores 55 marks. Write down and
solve an equation for the number of questions which James gets right

1 answer

(b)attempted question=22
left question=3
since the maximum mark can be obtained from attempted questions.
total mark can be obtained=22*4=88
since he has secured 55;so lost mark=88-55=33
since three question he has left;so three must be deducted from attempted question mark.
so 33-3=30
each wrong answer will deduct (4+2=6)marks.
so total no of question attempted but wrong=30/6=5
attempted question =22
so 22-5=17 is the correct ans