A test consists of ‘True’ or ‘False’ questions. One mark is awarded for every
correct answer while ¼ mark is deducted for every wrong answer. A student knew
answers to some of the questions. Rest of the questions he attempted by
guessing. He answered 120 questions and got 90 marks.
A) If answer to all questions he attempted by guessing were wrong, then how
many questions did he answer correctly?
B) How many questions did he guess?
C) If answer to all questions he attempted by guessing were wrong and
answered 80 correctly, then how many marks he got?