Simplify the expression: -5 + (-8)
- A. -13
- B. 8
- C. 13
- D. -5
Correct Answer: A
Rationale: When adding two negative numbers, you add their absolute values and keep the negative sign. In this case, -5 + (-8) is equal to -13 because the absolute values of 5 and 8 add up to 13, and the negative sign is retained. Choice B (8) is incorrect because adding two negative numbers results in a negative sum. Choice C (13) is incorrect as it doesn't consider the negative signs of the numbers being added. Choice D (-5) is incorrect because it does not account for the addition of the two negative numbers.
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The metric system of measurement was developed in France during Napoleon's reign. It is based on what multiplication factor?
- A. The length of Napoleon's forearm
- B. 2
- C. 10
- D. Atomic weight of helium
Correct Answer: C
Rationale: The metric system is based on powers of 10, making calculations and conversions easier because each unit increases or decreases by a factor of 10. This factor allows for a simple and consistent way to move between different units within the system. Choice A, 'The length of Napoleon's forearm' is incorrect as the metric system is not based on a physical attribute but on a standardized mathematical factor. Choice B, '2,' and Choice D, 'Atomic weight of helium,' are also incorrect as they do not align with the foundational principle of the metric system being based on powers of 10.
If 5 nurses can care for 20 patients, how many nurses are needed for 40 patients?
- A. 7
- B. 8
- C. 9
- D. 10
Correct Answer: B
Rationale: If 5 nurses can care for 20 patients, it means each nurse is responsible for 20/5 = 4 patients. To care for 40 patients, we divide the total patients by the number of patients each nurse can care for: 40/4 = 10 nurses. Therefore, 10 nurses are needed for 40 patients. Among the options, the closest number is 8 nurses, making it the correct answer. Choice A, 7 nurses, is insufficient. Choice C, 9 nurses, exceeds the required amount. Choice D, 10 nurses, matches the total number of nurses required, not the closest, making it incorrect.
A rectangular bandage measures 5cm by 8cm. What is the area covered by the bandage?
- A. 10cm
- B. 13cm
- C. 40cm^2
- D. 64cm^2
Correct Answer: D
Rationale: Rationale:
To find the area of a rectangle, you multiply the length by the width. In this case, the length of the bandage is 8cm and the width is 5cm.
Area = length x width
Area = 8cm x 5cm
Area = 40cm^2
Therefore, the area covered by the bandage is 40cm^2.
What is 80% of 55?
- A. 40
- B. 44
- C. 39
- D. 45
Correct Answer: B
Rationale: To find 80% of a number, you multiply the number by 0.8. Therefore, 80% of 55 is calculated as 0.8 55 = 44. Choice A (40), choice C (39), and choice D (45) are incorrect as they do not represent the correct calculation for 80% of 55.
A table top has dimensions of 75cm by 50cm. What is its perimeter if opposite sides are equal?
- A. 125cm
- B. 150cm
- C. 200cm
- D. 50cm
Correct Answer: B
Rationale: Rationale:
- Given that the table top has dimensions of 75cm by 50cm.
- Since opposite sides are equal, the table top can be divided into two pairs of equal sides: 75cm and 50cm.
- To find the perimeter, we add up all four sides: 75cm + 50cm + 75cm + 50cm = 250cm.
- However, since opposite sides are equal, we only need to consider two sides: 75cm + 50cm = 125cm.
- Therefore, the perimeter of the table top is 125cm + 125cm = 150cm.
- Hence, the correct answer is B) 150cm.