What is the mean for the data set 16, 18, 17, 15, 19, 14, 12, 11, 10, 16, 18, and 17?

Correct Answer: C

Rationale: To find the mean of a data set, you add up all the values and then divide by the total number of values. In this case, the sum of the data set is 185. Dividing this sum by the total number of values (12) gives you a mean of 16. Therefore, the correct answer is 16. Choice A (14.25), Choice B (15.25), and Choice D (17) are incorrect because they do not accurately represent the average value of the given data set.

Correct Answer: A

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

Correct Answer: A

Rationale: To multiply fractions, multiply the numerators together and the denominators together. Multiplying 3/5 by 5/7 gives (3*5)/(5*7) = 15/35. This fraction simplifies to 3/7 by dividing the numerator and denominator by their greatest common factor, which is 5. Therefore, the correct answer is 3/7. Choices B, C, and D are incorrect as they do not result from multiplying 3/5 by 5/7.

Correct Answer: C

Rationale: When you see something like (a + b)², it means you're multiplying (a + b) by itself: (a + b)² = (a + b) (a + b) To expand this, we use the distributive property (which says you multiply each term in the first bracket by each term in the second bracket): Multiply the first term in the first bracket (a) by both terms in the second bracket: a a = a² a b = ab Multiply the second term in the first bracket (b) by both terms in the second bracket: b a = ab b b = b² Now, add up all the results from the multiplication: a² + ab + ab + b² Since ab + ab is the same as 2ab, we can simplify it to: a² + 2ab + b² So, (a + b)² = a² + 2ab + b². This is known as a basic polynomial identity, and it shows that when you square a binomial (a two-term expression like a + b), you get three terms: the square of the first term (a²), twice the product of the two terms (2ab), and the square of the second term (b²). Therefore, the correct answer is C (a² + 2ab + b²)

Correct Answer: D

Rationale: When simplifying the expression 3x - 5x + 2, start by combining like terms. -5x is subtracted from 3x to give -2x. Adding 2 at the end gives the simplified expression -2x. Therefore, the correct answer is -2x. Choice A, -2x + 2, incorrectly adds 2 at the end. Choice B, -8x, incorrectly combines the coefficients of x without considering the constant term. Choice C, 2x + 2, incorrectly adds the coefficients of x without simplifying.