Complete the following equation: 2 + (2)(2) - 2 · 2 = ?
- A. 5
- B. 3
- C. 2
- D. 1
Correct Answer: A
Rationale: To solve the equation, follow the order of operations (PEMDAS/BODMAS): Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right).
1. Calculate inside the parentheses first: (2)(2) = 4.
2. Then, perform multiplication and division: 2 + 4 - 1 = 6 - 1 = 5.
Therefore, the correct answer is 5.
Choice B (3) is incorrect because multiplication is done before subtraction. Choices C (2) and D (1) are incorrect as they do not follow the correct order of operations to solve the equation.
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Simplify the following expression:
3 (1/6) - 1 (5/6)
- A. 2 (1/3)
- B. 1 (1/3)
- C. 2 (1/9)
- D. 5/6
Correct Answer: B
Rationale: To simplify:
First, subtract the whole numbers: 3 - 1 = 2.
Then, subtract the fractions: (1/6) - (5/6) = - (4/6) = - (2/3).
Now, subtract (2 - 2/3) = 1 (1/3).
Approximately what percentage more staff members at Hospital Y are female than at Hospital X?
- A. 5
- B. 10
- C. 15
- D. 20
Correct Answer: B
Rationale: To find the percentage more staff members at Hospital Y are female than at Hospital X, we first calculate the percentage of female staff members at each hospital. For Hospital Y: (90 / 183) x 100 ≈ 49.2%. For Hospital X: (97 / 250) x 100 ≈ 38.8%. The difference between these percentages is approximately 10%, making choice B the correct answer. Choice A, 5%, is too low as the difference is greater. Choice C, 15%, and choice D, 20%, are both too high as the actual difference is closer to 10%.
Mathew has to earn more than 96 points on his high school entrance exam in order to be eligible for varsity sports. Each question is worth 3 points, and the test has a total of 40 questions. Let x represent the number of test questions. How many questions can Mathew answer incorrectly and still qualify for varsity sports?
- A. x > 32
- B. x > 8
- C. 0 ≤ x < 8
- D. 0 ≤ x ≤ 8
Correct Answer: C
Rationale: To determine the number of correct answers Mathew needs, solve the inequality: 3x > 96. This simplifies to x > 32. Therefore, Mathew must answer more than 32 questions correctly to qualify for varsity sports. Since the test consists of 40 questions, he can afford to answer at most 40 - 32 = 8 questions incorrectly. Therefore, the correct answer is 0 ≤ x < 8. Option A (x > 32) is incorrect as it suggests Mathew needs to answer more than 32 questions correctly, which is not the case. Option B (x > 8) is also incorrect as it does not account for the total number of questions in the test. Option D (0 ≤ x ≤ 8) is incorrect as it includes the possibility of answering all questions incorrectly, which is not allowed for Mathew to qualify for varsity sports.
A patient was taking 310 mg of an antidepressant daily. The doctor reduced the dosage by 1/5, and then reduced it again by 20 mg. What is the patient's final dosage?
- A. 20 mg
- B. 42 mg
- C. 228 mg
- D. 248 mg
Correct Answer: C
Rationale: To calculate the final dosage, first find 1/5 of 310 mg, which is 62 mg, and subtract it from the original dosage. This gives 310 mg - 62 mg = 248 mg. Then, subtract an additional 20 mg from the result to get the final dosage: 248 mg - 20 mg = 228 mg. Therefore, the patient's final dosage is 228 mg. Choice A (20 mg) is incorrect because it only considers the second reduction of 20 mg and misses the initial reduction by 1/5. Choice B (42 mg) is incorrect as it miscalculates the reduction amounts. Choice D (248 mg) is incorrect as it does not account for the second reduction of 20 mg.
A book has a width of 2.5 decimeters. What is the width of the book in centimeters?
- A. 0.25 centimeters
- B. 25 centimeters
- C. 250 centimeters
- D. 0.025 centimeters
Correct Answer: B
Rationale: To convert decimeters to centimeters, we use the conversion factor that 1 decimeter is equal to 10 centimeters. Setting up the proportion: 1/0.1 = x/2.5. Solving for x gives 2.5 = 0.1x, x = 25. Therefore, the width of the book in centimeters is 25. Choices A, C, and D are incorrect because they do not correctly convert decimeters to centimeters. A and D have decimal placement errors, and C has an incorrect magnitude of centimeters.