The length of a rectangle is twice its width, and its area is equal to the area of a square with 12 cm sides. What will be the perimeter of the rectangle to the nearest whole number?
- A. 36 cm
- B. 46 cm
- C. 51 cm
- D. 56 cm
Correct Answer: A
Rationale: Let the width of the rectangle be x cm, and its length be 2x cm. The area of the rectangle is 2x * x = 2x², and the area of the square is 12² = 144 cm². Setting the areas equal gives 2x² = 144. Solving for x gives x = 6. Thus, the width is 6 cm, and the length is 12 cm. The perimeter is 2(6 + 12) = 36 cm. Therefore, the correct answer is 36 cm. Choice B, 46 cm, is incorrect because it does not match the calculated perimeter. Choices C and D are also incorrect as they do not reflect the correct calculation of the rectangle's perimeter.
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If a rat can finish a maze in about 3 minutes, how much longer will it take the rat to finish the maze if a small backpack is put on it, reducing its speed by 50%?
- A. 3 minutes
- B. 4 minutes
- C. 6 minutes
- D. 1.5 minutes
Correct Answer: C
Rationale: Reducing the rat's speed by 50% means it will take twice as long to finish the maze. Since the original time is 3 minutes, doubling that gives 6 minutes. Therefore, the total time will be 6 minutes, making the correct answer C. Choice A (3 minutes) is the original time it takes the rat to finish the maze, not the time with the backpack. Choice B (4 minutes) is not correct as reducing the speed by 50% would double the original time. Choice D (1.5 minutes) is incorrect as halving the time is not the effect of reducing the speed by 50%.
The physician orders 1000 mg of Benadryl liquid; 1 g = 1 tsp. How many teaspoons will you give?
- A. .75 tsp
- B. 1.5 tsp
- C. 1 tsp
- D. 1.25 tsp
Correct Answer: C
Rationale: Since 1 gram (g) equals 1000 milligrams (mg) and 1 g = 1 teaspoon (tsp), the prescribed 1000 mg is equal to 1 tsp. Therefore, you will give 1 teaspoon of the Benadryl liquid. Choices A, B, and D are incorrect because they do not correspond to the correct conversion of 1 g to 1 tsp, which is essential in solving this dosage calculation.
An IV drip delivers medication at a rate of 40 drops per minute. Each drop contains 0.05 milliliters of the medication. How many milliliters of medication are delivered in one hour?
- A. 12 milliliters
- B. 24 milliliters
- C. 60 milliliters
- D. 120 milliliters
Correct Answer: D
Rationale: To find the amount of medication delivered in one hour, we first calculate the amount delivered in one minute by multiplying the number of drops per minute (40) by the volume of each drop (0.05 milliliters). This gives us 2 milliliters per minute. Then, to find the total amount delivered in one hour, we multiply 2 milliliters per minute by the number of minutes in an hour (60), resulting in 120 milliliters. Therefore, the correct answer is 120 milliliters. Choices A, B, and C are incorrect as they do not correctly calculate the total volume of medication delivered in one hour.
A pressure vessel has a cylindrical body (diameter 10cm, height 20cm) with hemispherical ends (same diameter as the cylinder). What is its total surface area?
- A. 785 sq cm
- B. 1130 sq cm
- C. 1570 sq cm
- D. 2055 sq cm
Correct Answer: D
Rationale: To find the total surface area, we need to calculate the surface area of the cylindrical body and both hemispherical ends separately. The surface area of the cylinder is the sum of the lateral surface area (2πrh) and the area of the two circular bases (2πr^2). For the hemispheres, the surface area of one hemisphere is (2πr^2), so for two hemispheres, it would be (4πr^2). Given that the diameter of the cylinder and hemispherical ends is 10cm, the radius (r) is 5cm. Calculating the individual surface areas: Cylinder = 2π(5)(20) + 2π(5)^2 = 200π + 50π = 250π. Hemispheres = 4π(5)^2 = 100π. Adding these together gives a total surface area of 250π + 100π = 350π cm^2, which is approximately equal to 2055 sq cm. Therefore, the correct answer is D. Choice A (785 sq cm) is incorrect as it is significantly lower than the correct calculation. Choices B (1130 sq cm) and C (1570 sq cm) are also incorrect as they do not reflect the accurate surface area calculation for the given dimensions.
Which of the following is equivalent to 0.0009?
- A. 0.09%
- B. 9%
- C. 0.01%
- D. 0.90%
Correct Answer: A
Rationale: The correct answer is A: 0.09%. To convert 0.0009 to a percentage, move the decimal point four places to the right and add a percentage sign. Therefore, 0.0009 is equal to 0.09%. Choice B (9%) is incorrect as it represents 0.09 without the decimal point adjustment. Choice C (0.01%) is incorrect as it represents 0.0009 with one less zero. Choice D (0.90%) is incorrect as it represents 0.9 not 0.0009.
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