Adam scores a total of 40 marks.
There are a total of 80 questions.
Every correct answer will earn 4 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 |
80 |
80 x 4 = 320 |
0 |
320 |
79 |
79 x 4 = 316 |
1 |
316 |
10 |
10 x 4 = 40 |
70 |
40 |
(a)
Total score if Adam answers all the questions correctly
= 80 x 4
= 320
Total score if Adam answers one question wrongly
= 79 x 4
= 316
Big difference in marks deducted
= 320 - 40
= 280
Small difference in marks deducted
= 320 - 316
= 4
Number of questions answered incorrectly
= 280 ÷ 4
= 70
(b)
Number of questions answered correctly
= 80 - 70
= 10
Answer(s): (a) 70; (b) 10