Correct Answer: D

Rationale: To solve the equation 3(x - 1) = 2(3x - 9), first distribute and simplify both sides to get 3x - 3 = 6x - 18. Next, subtract 3x from both sides to get -3 = 3x - 18. Then, add 18 to both sides to obtain 15 = 3x. Finally, divide by 3 to find x = 5. Therefore, the correct answer is x = 5. Choices A, B, and C are incorrect because they do not represent the correct solution to the given equation after proper algebraic manipulation.

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%.

Correct Answer: C

Rationale: Erma receives a 25% discount on the $44 sweater, which amounts to a $11 discount. Therefore, she pays $44 - $11 = $33 for this sweater. Adding this discounted price to the $50 sweater, Erma will spend a total of $50 + $33 = $83. Choice A, $79, is incorrect because it does not include the correct calculation for the discounted sweater. Choice B, $81, is incorrect as it does not consider the discounts on both sweaters. Choice D, $85, is incorrect since it overestimates the total amount Erma will spend.

Correct Answer: D

Rationale: To solve the equation 3(x - 1) = 2(3x - 9), first distribute and simplify both sides to get 3x - 3 = 6x - 18. Next, subtract 3x from both sides to get -3 = 3x - 18. Then, add 18 to both sides to obtain 15 = 3x. Finally, divide by 3 to find x = 5. Therefore, the correct answer is x = 5. Choices A, B, and C are incorrect because they do not represent the correct solution to the given equation after proper algebraic manipulation.

Correct Answer: A

Rationale: To represent 'Four more than a number, x', we write x + 4. This is equal to '2 less than 1/3 of another number, y', which translates to 1/3y - 2. Therefore, the correct equation is x + 4 = (1/3)y - 2. Choice B is incorrect as it incorrectly combines the values of x and y. Choice C is incorrect as it doesn't properly relate x and y with the given conditions. Choice D is incorrect as it doesn't correctly represent the relationship between x and y according to the given statement.