Adam scores a total of 42 marks.
There are a total of 60 questions.
Every correct answer will earn 2 marks.
Every wrong answer will earn 0 marks.
How many questions are (a) incorrectly answered and (b) correctly answered?
Number of correct answers |
Marks earned |
Number of incorrect answers |
Total marks |
60 |
60 x 2 = 120 |
0 |
120 |
59 |
59 x 2 = 118 |
1 |
118 |
21 |
21 x 2 = 42 |
39 |
42 |
(a)
Total score if Adam answers all the questions correctly
= 60 x 2
= 120
Total score if Adam answers one question wrongly
= 59 x 2
= 118
Big difference in marks deducted
= 120 - 42
= 78
Small difference in marks deducted
= 120 - 118
= 2
Number of questions answered incorrectly
= 78 ÷ 2
= 39
(b)
Number of questions answered correctly
= 60 - 39
= 21
Answer(s): (a) 39; (b) 21