Solve for x: 4x + 2 = 18.

Correct Answer: B

Rationale: To solve for x, first, subtract 2 from both sides of the equation: 4x = 16. Then, divide by 4 to isolate x: x = 4. Choice A, x = 4, is the correct answer as calculated. Choice C, x = 5, is incorrect because the correct value of x is 4, not 5. Choice D, x = 3, is incorrect as well, as the correct value of x is 4, not 3.

Correct Answer: C

Rationale: To calculate the total number of words typed in 20 minutes, multiply the typing speed per minute (45 words) by the duration in minutes (20 minutes): 45 words/min 20 min = 900 words. Therefore, the correct answer is 900 words. Choices A, B, and D are incorrect because they do not reflect the accurate calculation based on the given information.

Correct Answer: A

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: A

Rationale: To subtract mixed numbers, find a common denominator. In this case, the common denominator is 20. Convert 15 3/4 to 15 15/20. Then, subtract 15 15/20 - 8 8/20 = 7 7/20. Therefore, the correct answer is A. Choice B is incorrect as it does not match the result of the subtraction. Choice C is incorrect as it is not the result of the subtraction. Choice D is incorrect as it represents the second number being subtracted, not the result of the subtraction.

Correct Answer: A

Rationale: To convert a fraction to a decimal, divide the numerator by the denominator. In this case, 3 divided by 4 is equal to 0.75. Therefore, the correct answer is A. Choices B, C, and D are incorrect because they do not represent the equivalent decimal value of 3/4. 0.5 is the decimal equivalent of 1/2, 0.65 is the decimal equivalent of 13/20, and 0.85 is the decimal equivalent of 17/20.