Final answer:
Whether the domain of a function includes all real numbers depends on the function and the data set involved. For instance, in functions based on money spent or specific x values, the domain is restricted. Hence, without the knowledge of the function and data, one cannot unconditionally claim that the domain includes all real numbers.
Step-by-step explanation:
The statement that the domain for the function is all real numbers may not always be true. Whether this is accurate or not depends on the specific function and data set being referred to. For example, if you have a function based on money spent, such as the one mentioned in the reference, the domain would only include positive numbers because you cannot spend a negative amount of money. Similarly, as per the reference, for a function based on x values between 65 and 75, 90 would be outside the domain of the observed x values. Furthermore, for a Discrete Random Variable, the domain might consist of specific items like a list of majors offered at a university and not all real numbers. Therefore, without specifying the function and the data set, one cannot definitively state that the domain is all real numbers.
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