20. For each additional hour spent studying after taking a practice exam, a student can expect to increase their final exam score by 5%. If a student scores 70% on the practice exam and then spends an additional 6 hours studying, which of the following is their expected score on the final exam?
Answer: C
The expected score on the final exam is 100%.
By studying for an additional 6 hours after scoring 70% on the practice exam, the student can expect to increase their final exam score by 30% (6 hours × 5% per hour), leading to a projected final score of 100%.
A) 73%
This option is incorrect because it suggests only a 3% increase from the practice exam score of 70%. Given that the student studies for 6 additional hours, the expected increase in score should be much higher, totaling a 30% increase.
B) 70%
This option is incorrect as it implies that the student would not benefit from additional study time. Since each hour of study results in a 5% increase, the student's final exam score should be significantly higher than their practice exam score of 70%.
C) 100%
This option is correct because after studying for 6 additional hours, the student would gain a total of 30% (6 hours × 5% per hour) added to their initial score of 70%. This results in a final exam score of 100%, as it is the maximum possible score.
D) 75%
This option is incorrect since it only reflects a 5% increase from the practice exam score. With the additional 6 hours of study, the expected score should be considerably higher, reaching a maximum of 100%.
Conclusion
The analysis clearly shows that with 6 hours of studying, the expected increase in exam score is 30%, leading to a final score of 100%. All other options either underestimate the benefits of studying or miscalculate the final score, confirming that C is the only correct answer.