During one exam, points were awarded for questions answered as shown.
|
Points per question |
Correct |
7 |
Wrong |
- 3 |
Missed |
- 1 |
The ratio of the questions correctly to questions answered wrongly to questions that were missed out was 10 : 3 : 1. If Natalie was awarded 420 points, how many questions are there in all?
|
Correct |
Wrong |
Missed |
Number |
10 u |
3 u |
1 u |
Value |
7 |
- 3 |
- 1 |
Total value |
70 u |
9 u |
1 u |
Total score that Natalie was awarded
= 70 u - 9 u - 1 u
= 60 u
60 u = 420
1 u = 420 ÷ 60 = 7
Total number of questions
= 10 u + 3 u + 1 u
= 14 u
= 14 x 10
= 140
Answer(s): 140