Simplify the expression below. Which of the following is correct? 3.45 * 0.53

Correct Answer: A

Rationale: To solve 3.45 * 0.53, multiply the numbers to get 1.8285. Therefore, the correct answer is A. Choice B is incorrect because it incorrectly moves the decimal point. Choice C is incorrect as it is a fraction of the correct answer. Choice D is incorrect as it results from an error in moving the decimal point.

Correct Answer: A

Rationale: An exponent is a number that indicates how many times a base number is multiplied by itself. The correct answer (A) accurately defines an exponent as a multiplier that shows how many times a number should be multiplied by itself. Choice B is incorrect as it describes a factor rather than an exponent. Choice C is incorrect as it defines a divisor, not an exponent. Choice D is incorrect as it specifically refers to the square of a number, which is not a general definition of an exponent.

Correct Answer: A

Rationale: After the $400 down payment, the remaining balance is $1,170. With monthly payments of $100, it will take 12 months to pay off the remaining balance. Therefore, the correct answer is 12 months. Choice B (16) is incorrect as it exceeds the required timeframe. Choice C (15) is incorrect as it is close but still one month over the correct timeframe. Choice D (11) is incorrect as it underestimates the time needed to pay off the remaining balance.

Correct Answer: B

Rationale: The total cost (T) consists of the initial charge of $40 plus the additional charges based on the number of tablecloths. The correct expression for T is T = 5c + 3.5r + 40. This accounts for the $5 per circular tablecloth (5c), $3.50 per rectangular tablecloth (3.5r), and the initial $40 charge. Choice A is incorrect as it subtracts the initial charge instead of adding it. Choice C is also incorrect as it subtracts the initial charge and has the coefficients in the wrong positions. Choice D adds the initial charge at the end instead of at the beginning, making it incorrect. Therefore, choice B is the correct representation of the total cost to rent tablecloths.

Correct Answer: A

Rationale: Rational numbers are those that can be written as a simple fraction, including whole numbers and decimals that either terminate or repeat. Irrational numbers, on the other hand, cannot be expressed as fractions. Choice B is incorrect because not all rational numbers necessarily terminate or repeat. Choice C is incorrect as it oversimplifies the concept of rational and irrational numbers by only considering whole numbers and decimals. Choice D is incorrect as it inaccurately defines rational and irrational numbers solely based on decimals terminating or repeating, excluding the broader category of fractions.

Correct Answer: A

Rationale: To solve the equation 3(x-2)=12, first distribute the 3: 3x - 6 = 12. Next, isolate x by adding 6 to both sides: 3x = 18. Finally, divide by 3 to find x: x = 6. Therefore, the correct answer is A (6). Choice B (-2) is incorrect as it does not satisfy the equation. Choice C (-4) is also incorrect as it does not satisfy the equation. Choice D (2) is incorrect as it does not satisfy the equation either.

Correct Answer: A

Rationale: An equivalent fraction is a fraction that may look different in terms of its numerator and denominator but still represents the same value or quantity. This means that when you simplify or expand a fraction, its value remains unchanged. Choice B and C are incorrect because equivalent fractions are not determined by being smaller or larger than another fraction; it is about representing the same quantity. Choice D is incorrect because equivalent fractions may have different numerators as long as the ratio between the numerator and denominator remains the same.

Correct Answer: C

Rationale: The correct answer is C: 'As elevation increases, temperature decreases.' In a negative correlation, the variables move in opposite directions. As elevation rises, temperature tends to decrease. Choice A is incorrect because a negative correlation implies that as one variable increases, the other decreases. Choices B and D are incorrect because they suggest that temperature either remains the same or increases as elevation decreases or increases, which is inconsistent with a negative correlation.

Correct Answer: A

Rationale: The ratio 4:3 implies that for every 4 oz of yogurt, there are 3 oz of toppings. To find the amount of yogurt when the friend has 4.5 oz of toppings, we use the proportion: (4/3) 4.5 = 6 oz. Therefore, the amount of yogurt in their dessert is 6 oz. Choices B, C, and D are incorrect as they do not reflect the correct calculation based on the given ratio.