In a graph that shows the number of nurses in various specialties, what is the independent variable?
- A. Anesthesia
- B. Geriatrics
- C. Nurse specialties
- D. Number of nurses
Correct Answer: C
Rationale: The independent variable is the variable that is controlled or manipulated in an experiment or study. In this case, the independent variable is the nurse specialties because it is the factor that is being observed and measured to see how it affects the number of nurses in each specialty. The dependent variable, which changes in response to the independent variable, is the number of nurses. Choices A and B are specific nurse specialties and are actually part of the data being measured, not the independent variable itself. Choice D, 'Number of nurses,' is the dependent variable as it is the outcome that is being influenced by the independent variable, which is the nurse specialties.
You may also like to solve these questions
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.
The cost of renting a bicycle is $3.60 per hour. Which equation shows the best relationship between the total cost (C) and the number of hours (h) rented?
- A. C = 3.60h
- B. C = h + 3.60
- C. C = 3.60h + 10.80
- D. C = 10.80h
Correct Answer: A
Rationale: The best relationship is C = 3.60h because the cost increases by $3.60 for each hour of rental. This equation represents a linear relationship where the total cost (C) is directly proportional to the number of hours rented (h). Choice B (C = h + 3.60) is incorrect because it wrongly assumes a fixed additional cost of $3.60 regardless of the number of hours rented. Choice C (C = 3.60h + 10.80) is incorrect as it overestimates the initial cost. Choice D (C = 10.80h) is incorrect as it implies a constant rate of $10.80 per hour, which is not the case.
What is the probability of flipping a coin and getting heads?
- A. 1/2
- B. 1/3
- C. 1/4
- D. 1/5
Correct Answer: A
Rationale: The correct answer is A: 1/2. When flipping a fair coin, there are two possible outcomes: heads or tails. The probability of getting heads is 1 out of 2 possible outcomes, which can be expressed as 1/2. Choice B, 1/3, is incorrect because a fair coin only has two sides. Choices C and D, 1/4 and 1/5, are also incorrect as they do not represent the correct probability of getting heads when flipping a coin.
In a research study, a researcher collects data on the number of hours spent studying and the grades students received. Which of the following is the dependent variable?
- A. The number of hours spent studying
- B. The grades students received
- C. The subjects students studied
- D. The number of students in the study
Correct Answer: B
Rationale: The correct answer is B: 'The grades students received.' In this scenario, the grades students received are the dependent variable because they are influenced by the number of hours spent studying. The grades are the outcome that is being measured based on the manipulation or observation of the independent variable, which in this case is the number of hours spent studying. Choices A, C, and D are incorrect. The number of hours spent studying is the independent variable being manipulated or observed, the subjects students studied is not directly related to the dependent variable, and the number of students in the study is not the variable being measured or influenced by the independent variable.
A charter bus driver drove at an average speed of 65 mph for 305 miles. If he stops at a gas station for 15 minutes, then drives another 162 miles at an average speed of 80 mph, how long will it have been since he began the trip?
- A. 0.96 hours
- B. 6.44 hours
- C. 6.69 hours
- D. 6.97 hours
Correct Answer: D
Rationale: To find the total time, we first calculate the time taken for the first leg of the trip by dividing the distance of 305 miles by the speed of 65 mph, which equals 4.69 hours. After that, we add the 15 minutes spent at the gas station, which is 0.25 hours. Next, we calculate the time taken for the second leg of the trip by dividing the distance of 162 miles by the speed of 80 mph, which equals 2.03 hours. Adding these times together (4.69 hours + 0.25 hours + 2.03 hours) gives us a total time of 6.97 hours. Therefore, it will have been 6.97 hours since the driver began the trip. Choice A is incorrect as it does not account for the time spent driving the second leg of the trip. Choice B is incorrect as it only considers the time for the first leg of the trip and the time spent at the gas station. Choice C is incorrect as it misses the time taken for the second leg of the trip.