Adam scores a total of 40 marks.
There are a total of 50 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 |
50 |
50 x 2 = 100 |
0 |
100 |
49 |
49 x 2 = 98 |
1 |
98 |
20 |
20 x 2 = 40 |
30 |
40 |
(a)
Total score if Adam answers all the questions correctly
= 50 x 2
= 100
Total score if Adam answers one question wrongly
= 49 x 2
= 98
Big difference in marks deducted
= 100 - 40
= 60
Small difference in marks deducted
= 100 - 98
= 2
Number of questions answered incorrectly
= 60 ÷ 2
= 30
(b)
Number of questions answered correctly
= 50 - 30
= 20
Answer(s): (a) 30; (b) 20