Question

In a multiple choice examination of 20 questions, 4 marks are given for every correct answer and one mark is deducted for each wrong answer. There is no penalty for not attempting a question. A candidate attemps 'a' questions and gets 'c' correct.
(i) Write down, and simplify, an expression for the candidate's total mark in terms of 'a' and 'c'.
(ii) A candidate attempts 3/4 of the questions and scores 40. Write down, and solve, an equation for the number of correct questions.

Answer 1

Please help! :)

Answer 2

4c - 3(a-c) = grade?

Answer 3

1 mark, not 3 ....

Answer 4

4c - (a-c) = grade

if i see it right