Which of the following is the correct solution to the equation 3x + 4 = 19?
- A. x = 3
- B. x = 4
- C. x = 5
- D. x = 6
Correct Answer: C
Rationale: To solve the equation 3x + 4 = 19, first, subtract 4 from both sides to isolate the term with x, which gives 3x = 15. Then, divide both sides by 3 to solve for x, resulting in x = 5. Therefore, the correct answer is x = 5. Choice A, x = 3, is incorrect as it does not satisfy the equation. Choice B, x = 4, is also incorrect as it does not make the equation true. Choice D, x = 6, is incorrect as it does not align with the correct solution obtained through the proper algebraic steps.
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The owner of a newspaper has noticed that print subscriptions have gone down 40% while online subscriptions have gone up 60%. Print subscriptions once accounted for 70% of the newspaper's business, and online subscriptions accounted for 25%. What is the overall percentage growth or decline in business?
- A. 13% decline
- B. 15% decline
- C. 28% growth
- D. 8% growth
Correct Answer: A
Rationale: To calculate the decline in business, start with the 40% decline in the 70% share of print subscriptions: 40% of 70% = 0.40 0.70 = 0.28 = 28% decline. Next, calculate the growth from the 60% increase in the 25% share of online subscriptions: 60% of 25% = 0.60 0.25 = 0.15 = 15% growth. To find the overall change, sum the decline and growth percentages: 28% decline + 15% growth = -0.28 + 0.15 = -0.13 = 13% decline. Therefore, the overall percentage change in the newspaper's business is a 13% decline. Option A is the correct answer. Option B is incorrect because it doesn't consider the correct calculations for both the decline and growth. Option C is incorrect as it misinterprets the net change in business. Option D is incorrect as it miscalculates the overall percentage growth or decline.
If m represents a car's average mileage in miles per gallon, p represents the price of gas in dollars per gallon, and d represents a distance in miles, which of the following algebraic equations represents the cost, c, of gas per mile?
- A. c = dp/m
- B. c = p/m
- C. c = mp/d
- D. c = m/p
Correct Answer: B
Rationale: The cost of gas per mile, c, is calculated by dividing the price of gas, represented by p, by the car's average mileage, represented by m. Therefore, the correct equation is c = p/m. Choice A (dp/m) incorrectly multiplies the price of gas and distance, while choice C (mp/d) incorrectly multiplies the average mileage and price of gas. Choice D (m/p) incorrectly divides the average mileage by the price of gas, which does not represent the cost of gas per mile.
A car dealership's commercials claim that this year's models are 20% off the list price, plus they will pay the first 3 monthly payments. If a car is listed for $26,580, and the monthly payments are set at $250, what is the total potential savings?
- A. $1,282
- B. $5,566
- C. $6,066
- D. $20,514
Correct Answer: C
Rationale: To calculate the total potential savings: First, find the 20% discount on the list price of $26,580: 0.20 $26,580 = $5,316. Then, determine the savings over the first 3 months of payments: 3 months $250/month = $750. Add the discount and the monthly payment savings to get the total potential savings: $5,316 + $750 = $6,066. Therefore, the correct answer is $6,066. Choice A, $1,282, is incorrect because it does not account for the total savings from both the discount and the monthly payments. Choice B, $5,566, is incorrect as it miscalculates the total savings by excluding the savings from the monthly payments. Choice D, $20,514, is incorrect as it does not consider the discount and only focuses on the list price.
Which of the following is equivalent to 8 pounds and 8 ounces? (Round to the nearest tenth of a kilogram.)
- A. 3.6 kilograms
- B. 3.9 kilograms
- C. 17.6 kilograms
- D. 18.7 kilograms
Correct Answer: B
Rationale: To convert 8 pounds and 8 ounces to kilograms, first convert 8 ounces to pounds by dividing by 16 (since 1 pound = 16 ounces): 8 ounces / 16 = 0.5 pounds. Then add this to the original 8 pounds: 8 pounds + 0.5 pounds = 8.5 pounds. To convert pounds to kilograms, use the conversion factor 1 pound = 0.453592 kilograms. Therefore, 8.5 pounds 0.453592 kg = 3.855 kilograms, which rounds to 3.9 kilograms. Choice A (3.6 kilograms), Choice C (17.6 kilograms), and Choice D (18.7 kilograms) are incorrect conversions or have errors in calculation compared to the correct conversion of 3.9 kilograms.
A woman's dinner bill comes to $48.30. If she adds a 20% tip, which of the following will be her total bill?
- A. $9.66
- B. $38.64
- C. $48.30
- D. $57.96
Correct Answer: D
Rationale: To calculate the total bill after adding a 20% tip, you need to find 120% of the original bill. This is because adding a 20% tip means paying 120% of the bill. So, $48.30 120/100 = $57.96. Therefore, the correct answer is $57.96. Choice A ($9.66) is incorrect as it represents only the 20% tip amount. Choice B ($38.64) is incorrect as it is the original bill amount without the tip. Choice C ($48.30) is incorrect as it is the original bill amount and does not include the additional 20% tip.