Correct Answer: C

Rationale: To find out how many words a person can type in 20 minutes at a speed of 45 words per minute, you multiply the typing speed (45 words/minute) by the duration (20 minutes): 45 words/minute x 20 minutes = 900 words. Hence, the correct answer is 900 words. Choice A (800 words) is incorrect because it results from multiplying 45 words per minute by 18 minutes, not 20. Choice B (850 words) is incorrect as it is not the product of 45 words per minute and 20 minutes. Choice D (750 words) is incorrect because it is the outcome of multiplying 45 words per minute by 15 minutes, not 20.

Correct Answer: C

Rationale: To solve the equation 8x = x^2, rearrange it to x^2 - 8x = 0. Factor out an x to get x(x - 8) = 0. Set each factor to zero to find the solutions: x = 0 or x = 8. Therefore, x = 16 is the correct answer because x = 0 is not in the answer choices, and x = 8 is a distraction meant to confuse. Thus, choice C, 16, is the correct solution to the equation.

Correct Answer: A

Rationale: To convert liters to milliliters, remember there are 1,000 milliliters in a liter. So, to find how many milliliters are in 5 liters, you multiply 5 (liters) by 1,000 (milliliters per liter), which equals 5,000 milliliters. Choice A is correct as it converts 5 liters to milliliters accurately. Choice B, 50 milliliters, is incorrect as it mistakenly converts liters to milliliters by a factor of 100 instead of 1,000. Choice C, 500 milliliters, is incorrect as it also wrongly converts liters to milliliters by a factor of 10 instead of 1,000. Choice D, 0.5 milliliters, is incorrect as it inaccurately converts 5 liters to 0.5 milliliters, which is not correct.

Correct Answer: A

Rationale: To convert 0.025 to a ratio, we can express it as 25:1000 and simplify it by dividing both terms by 25, resulting in 1:40. Therefore, the correct answer is A. Choice B (4:1) and C (400:1) do not represent the correct ratio for 0.025. Choice D (26:40:00) is incorrect as it does not follow the standard ratio format of two numbers separated by a colon.

Correct Answer: C

Rationale: To convert the fraction 7/8 to a decimal, you divide the numerator (7) by the denominator (8): 7 · 8 = 0.875. Therefore, the correct decimal representation of the fraction 7/8 is 0.875. Choice A and B, which are both 0.8, are incorrect as they represent 4/5 and not 7/8. Choice D, 0.9, is also incorrect as it represents 9/10 and not 7/8.