Which of the following describes a proportional relationship?
- A. Johnathan opens a savings account with an initial deposit of $150 and deposits $125 per month
- B. Bruce pays his employees $12 per hour worked during the month of December, as well as a $250 bonus
- C. Alvin pays $28 per month for his phone service plus $0.07 for each long-distance minute used
- D. Kevin drives 65 miles per hour
Correct Answer: A
Rationale: A proportional relationship is one in which two quantities vary directly with each other. In choice A, the amount deposited per month is directly proportional to the initial deposit. The relationship can be represented as y = 125x + 150, where x is the number of months and y is the total amount in the account. Choices B and C involve additional fixed amounts or variable costs that do not maintain a constant ratio, making them non-proportional relationships. Choice D refers to a constant speed of driving, which is not a proportional relationship as it does not involve varying quantities that change in direct proportion.
You may also like to solve these questions
What is the number of students who said their favorite color is blue if 35% of 100 students chose blue as their favorite color?
- A. 35
- B. 25
- C. 20
- D. 10
Correct Answer: A
Rationale: To find the number of students who said their favorite color is blue, we calculate 35% of 100, which is (35/100) * 100 = 35. Therefore, 35 students said their favorite color is blue. Choice B is incorrect because it represents the percentage of students who chose red. Choice C is incorrect as it represents the percentage of students who chose green. Choice D is incorrect as it represents the percentage of students who chose yellow.
Dr. Lee observed that 30% of all his patients developed an infection after taking a certain antibiotic. He further noticed that 5% of that 30% required hospitalization to recover from the infection. What percentage of Dr. Lee's patients were hospitalized after taking the antibiotic?
- A. 1.50%
- B. 5%
- C. 15%
- D. 30%
Correct Answer: A
Rationale: To find the percentage of Dr. Lee's patients hospitalized after taking the antibiotic, we need to calculate 30% of 5%. First, convert 30% and 5% to decimals: 30% = 0.30 and 5% = 0.05. Multiply 0.30 by 0.05 to get 0.015. To convert 0.015 to a percentage, multiply by 100, resulting in 1.5%. Therefore, only 1.50% of Dr. Lee's patients were hospitalized after taking the antibiotic. Choice A is correct. Choice B (5%) is incorrect as it represents the percentage of patients who developed an infection and not those hospitalized. Choices C (15%) and D (30%) are also incorrect percentages as they do not accurately reflect the proportion of hospitalized patients in this scenario.
A farmer had about 150 bags of potatoes on his trailer. Each bag contained from 23 to 27 pounds of potatoes. What is the best estimate of the total number of pounds of potatoes on the farmer's trailer?
- A. 3,000 pounds
- B. 3,700 pounds
- C. 4,100 pounds
- D. 5,000 pounds
Correct Answer: B
Rationale: To estimate the total number of pounds of potatoes on the farmer's trailer, we can use the average weight of a bag of potatoes. The average weight is calculated by adding the minimum and maximum weights of the bags and dividing by 2: (23 + 27) / 2 = 25 pounds. Next, multiply the average weight by the total number of bags: 25 pounds/bag * 150 bags = 3,750 pounds. Therefore, the best estimate of the total number of pounds of potatoes on the farmer's trailer is 3,750 pounds. Choice A (3,000 pounds) is too low as it underestimates the total weight. Choice C (4,100 pounds) and Choice D (5,000 pounds) are too high as they overestimate the total weight.
Which of the following is listed in order from least to greatest? (-3/4, -7 4/5, -8, 18%, 0.25, 2.5)
- A. -3/4, -7 4/5, -8, 18%, 0.25, 2.5
- B. -8, -7 4/5, -3/4, 18%, 0.25, 2.5
- C. 18%, 0.25, -3/4, 2.5, -7 4/5, -8
- D. -8, -7 4/5, -3/4, 18%, 0.25, 2.5
Correct Answer: D
Rationale: To arrange the numbers from least to greatest, we first compare the integers, then the fractions, and finally the percentages and decimals. The correct order is -8, -7 4/5, -3/4, 18%, 0.25, 2.5. Choice A is incorrect because it incorrectly orders the fractions. Choice B is incorrect because it incorrectly places -8 after the fractions. Choice C is incorrect because it starts with the percentages instead of the integers, leading to an incorrect order.
A patient requires a 30% decrease in their medication dosage. Their current dosage is 340 mg. What will their dosage be after the decrease?
- A. 70 mg
- B. 238 mg
- C. 270 mg
- D. 340 mg
Correct Answer: B
Rationale: To calculate a 30% decrease of 340 mg, multiply 340 by 0.30 to get 102. Subtracting 102 from 340 gives a new dosage of 238 mg. Choice A (70 mg) is incorrect as it represents a 80% decrease, not 30%. Choice C (270 mg) is incorrect as it does not reflect a decrease but rather the original dosage. Choice D (340 mg) is incorrect as it is the original dosage and not reduced by 30%.
Nokea