What must you always use in all math?

Correct Answer: A

Rationale: The correct answer is A: PEMDAS. PEMDAS stands for the order of operations: Parentheses, Exponents, Multiplication and Division (left to right), Addition and Subtraction (left to right). It is a fundamental rule to follow in mathematics to ensure calculations are done correctly. Choices B, C, and D are incorrect as they do not encompass the essential rule that PEMDAS provides for solving mathematical expressions.

Correct Answer: C

Rationale: The least common denominator of two fractions is the least common multiple of both denominators. This is because the least common denominator is the smallest number that both denominators can divide into evenly, ensuring that both fractions can be expressed with a common denominator. Choice A is incorrect as the least common denominator is a multiple of both denominators, not a number that multiplies into both. Choice B is incorrect because the common denominator needs to be a multiple of both denominators, not just a number they can divide into evenly. Choice D is incorrect as the greatest common factor is not used to find the least common denominator, but rather the least common multiple.

Correct Answer: B

Rationale: Histograms are specifically designed to display the frequency distribution of continuous data, showing the distribution of values over intervals or bins. On the other hand, bar graphs are used to compare different categories or discrete data points. Therefore, the correct answer is B. Choices A, C, and D are incorrect because histograms are not primarily used for comparing categories, percentages, or proportions, but rather for visualizing the distribution of frequencies within data intervals.

Correct Answer: A

Rationale: The key difference between a histogram and a bar graph is that a bar graph has gaps between the bars, while a histogram does not. This feature helps in visually distinguishing between the two. Choice B is incorrect because both types of graphs can show frequency. Choice C is incorrect as both graphs can be used for comparison. Choice D is incorrect as both types of graphs can have labels for better understanding.

Correct Answer: A

Rationale: Correct Answer: Ranges. Histograms utilize ranges (intervals) to display the frequency distribution of continuous data, highlighting the frequency of values falling within each interval. Bar graphs, on the other hand, represent discrete data using separate and distinct bars to show comparisons between different categories or groups. Choice B (Categories) is incorrect because both histograms and bar graphs can display data based on categories, but histograms use ranges to group continuous data. Choice C (Labels) is incorrect as both types of graphs can have labels to provide context and information. Choice D (Percentages) is incorrect because percentages can be used in both histograms and bar graphs to show proportions, but they are not a defining feature that distinguishes histograms from bar graphs.