Adam scores a total of 53 marks.
There are a total of 29 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
|
29 |
29 x 4 = 116 |
0 |
0 |
116 - 0 = 116 |
28 |
28 x 4 = 112 |
1 |
1 x 3 = 3 |
112 - 3 = 109 |
20 |
80 |
9 |
9 x 3 = 27 |
80 - 27 = 53 |
(a)
Total score if Adam answers all the questions correctly
= 29 x 4
= 116
Total score if Adam answers one question wrongly
= 112 - 3
= 109
Big difference in total score
= 116 - 53
= 63
Small difference in total score
= 4 + 3
= 7
Number of questions answered incorrectly
= 63 ÷ 7
= 9
(b)
Number of questions answered correctly
= 29 - 9
= 20
Answer(s): (a) 9; (b) 20