Adam scores a total of 77 marks.
There are a total of 28 questions.
Every correct answer will earn 4 marks.
Every blank or wrong answer will have 3 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
|
28 |
28 x 4 = 112 |
0 |
0 |
112 - 0 = 112 |
27 |
27 x 4 = 108 |
1 |
1 x 3 = 3 |
108 - 3 = 105 |
23 |
92 |
5 |
5 x 3 = 15 |
92 - 15 = 77 |
(a)
Total score if Adam answers all the questions correctly
= 28 x 4
= 112
Total score if Adam answers one question wrongly
= 108 - 3
= 105
Big difference in total score
= 112 - 77
= 35
Small difference in total score
= 4 + 3
= 7
Number of questions answered incorrectly
= 35 ÷ 7
= 5
(b)
Number of questions answered correctly
= 28 - 5
= 23
Answer(s): (a) 5; (b) 23