Final answer:
To find the percentage of questions answered incorrectly by an engineering student, subtract the number of correct answers from the total number of questions, and then calculate the percentage. The student answered 9 out of 90 questions incorrectly, which is 10% of the test.
Step-by-step explanation:
The question is asking to calculate the percentage of questions that an engineering student answered incorrectly on a test. The student answered 81 out of 90 questions correctly. To find the percentage of incorrect answers, we first calculate the number of questions answered incorrectly: 90 questions total minus 81 questions correct equals 9 questions incorrect.
Next, to find the percentage of incorrect answers, we use the following formula: (number of incorrect answers / total number of questions) × 100%. Plugging in our numbers: (9 / 90) × 100% = 10%. Therefore, the percentage of questions the student answered incorrectly is 10%.
The correct answer to the multiple-choice question is A) 10%.
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