12 is a/an:

Correct Answer: A

Rationale: In mathematics, the number 12 is classified as an even number. An even number is defined as any integer that is exactly divisible by 2, meaning when divided by 2, there is no remainder. In the case of 12, it can be divided evenly by 2, resulting in 6, making it an even number. Regarding the other options: - B) Odd numbers are integers that are not divisible by 2 without leaving a remainder. Since 12 can be divided by 2 without a remainder, it is not an odd number. - C) Prime numbers are integers greater than 1 that have exactly two distinct positive divisors: 1 and the number itself. 12 has divisors other than 1 and itself (1, 2, 3, 4, 6, and 12), so it is not a prime number. - D) Composite numbers are integers greater than 1 that are not prime, meaning they have more than two distinct positive divisors. Since 12 has multiple divisors as mentioned above, it falls under the category of a composite number. In an educational context, understanding the classification of numbers like even, odd, prime, and composite is fundamental in developing a strong foundation in mathematics. Recognizing the characteristics of each type of number helps students grasp concepts such as divisibility, factorization, and number properties, which are essential in higher-level math studies and problem-solving. By identifying 12 as an even number and differentiating it from odd, prime, and composite numbers, students can enhance their number sense and mathematical reasoning skills.

Correct Answer: A

Rationale: To solve for x, use cross-multiplication: 6x = 10 x 24 6x = 240 Now, divide both sides by 6 to find x: x = 240 / 6 = 40 Therefore, the correct answer is A. 40. Choice B, 25, is incorrect because it does not satisfy the proportion. Choice C, 240, is incorrect because it represents the value that is given in the proportion and not the value of x. Choice D, 4, is incorrect as it does not align with the correct calculation for x.

Correct Answer: A

Rationale: Substitute x=11 into the expression: 11 + (44 / 2*11) = 11 + (44 / 22) = 11 + 2 = 13 Therefore, the correct answer is 13. Choice A (2.5) is incorrect as the correct result is 13, not 2.5. Choice B (33) is incorrect because it does not result from the given expression. Choice C (55) is incorrect as it does not match the calculated value. Choice D (13) is incorrect because the correct solution is 13, not 2.5.

Correct Answer: A

Rationale: To solve the proportion x/250 = 3/500, cross multiply to get 500x = 750. Then solve for x by dividing both sides by 500, which results in x = 1.5. Therefore, the correct answer is A. Choice B (2) is incorrect because the correct solution is 1.5, not 2. Choice C (1500) is incorrect as it does not align with the correct calculation of the proportion. Choice D (25) is incorrect and does not match the correct solution obtained by solving the proportion.

Correct Answer: A

Rationale: To compare, convert both to decimals or percentages: Sally ate 3/5, which is 0.6 or 60%. John ate 75%. Since 75% is greater than 60%, John ate more than Sally. Thus, the correct answer is A. John. Choice B is incorrect because Sally ate a smaller percentage of her lunch compared to John. Choice C is incorrect as the percentages consumed are different. Choice D is incorrect as one of them ate more.