Final answer:
To decide what number sentence to write, understand the context, use problem-solving skills to identify and solve the problem, and utilize tools like calculators for precise calculations.
Step-by-step explanation:
Deciding what number sentence to write for an exercise involves understanding the relationship between the numbers and the context of the problem. For example, if the exercise is about solving linear equations, you might be given certain data points and be asked to write the linear equation that fits them. This typically involves entering your data into a calculator or computer, using functions to process the data, and then rounding results to four decimal places. When dealing with problem-and-solution paragraphs in mathematical context, you identify the problem (what you're trying to solve for) and then apply mathematical operations to solve it. If the exercise is more open-ended, then you might cover up one number, using the other given information to derive the missing value through algebraic manipulations or logical reasoning.