What is the result of (6.4)(2.8) · 0.4? Which of the following is correct?
- A. 16.62
- B. 17.92
- C. 41.55
- D. 44.8
Correct Answer: D
Rationale: To simplify the expression, first multiply 6.4 by 2.8 to get 17.92. Then, divide the result by 0.4 to find the final answer. Therefore, (6.4)(2.8) · 0.4 equals 44.8. Choices A, B, and C are incorrect because they do not represent the correct result of the given expression.
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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 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.
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.
Simplify the expression. What is the value of x? (5/4)x = 20
- A. 8
- B. 16
- C. 24
- D. 32
Correct Answer: D
Rationale: To solve for x, multiply both sides by the reciprocal of 5/4 to isolate x. (4/5)(5/4)x = (4/5)20; x = 16. Therefore, the correct answer is 32. Choice A (8), Choice B (16), and Choice C (24) are incorrect as they do not represent the correct value of x obtained after correctly simplifying the expression.
Adam is painting the outside of a 4-walled shed. The shed is 5 feet wide, 4 feet deep, and 7 feet high. Which of the following is the amount of paint Adam will need for the four walls?
- A. 80 ft²
- B. 126 ft²
- C. 140 ft²
- D. 560 ft²
Correct Answer: B
Rationale: To find the amount of paint needed for the four walls of the shed, calculate the total area of the four walls. The shed has two pairs of identical walls. The area of one pair of walls is 5 feet (width) x 7 feet (height) + 4 feet (depth) x 7 feet (height) = 35 ft² + 28 ft² = 63 ft². Since there are two pairs of walls, the total area for the four walls is 2 x 63 ft² = 126 ft². Therefore, Adam will need 126 ft² of paint for the four walls. Choice A, 80 ft², is incorrect as it does not account for the total surface area of all four walls. Choice C, 140 ft², is incorrect as it overestimates the area required. Choice D, 560 ft², is incorrect as it significantly overestimates the amount of paint needed for the shed.