Adam scores a total of 130 marks.
There are a total of 40 questions.
Every correct answer will earn 4 marks.
Every blank or wrong answer will have 2 marks deducted.
How many questions are (a) incorrectly answered and (b) correctly answered?
Number of correct answers |
Marks earned
|
Number of incorrect answers |
Marks deducted
|
Total score
|
40 |
40 x 4 = 160 |
0 |
0 |
160 - 0 = 160 |
39 |
39 x 4 = 156 |
1 |
1 x 2 = 2 |
156 - 2 = 154 |
35 |
140 |
5 |
5 x 2 = 10 |
140 - 10 = 130 |
(a)
Total score if Adam answers all the questions correctly
= 40 x 4
= 160
Total score if Adam answers one question wrongly
= 156 - 2
= 154
Big difference in total score
= 160 - 130
= 30
Small difference in total score
= 4 + 2
= 6
Number of questions answered incorrectly
= 30 ÷ 6
= 5
(b)
Number of questions answered correctly
= 40 - 5
= 35
Answer(s): (a) 5; (b) 35