In Mathematics, why is estimation considered a useful skill?

Estimation is regarded as a valuable skill in mathematics because it enables individuals to quickly assess the reasonableness of answers. When solving problems, especially in real-world situations, having a general idea of what the answer should be allows one to identify whether a solution is plausible. For instance, if you estimate that the result of a calculation involving large numbers should be in the thousands, but you arrive at something in the hundreds, you can recognize that there may have been an error in your computation. This process helps in verifying calculations without requiring the exact answer, making it especially useful in settings where time is limited or where an approximate answer suffices.

Options that suggest guaranteed correct answers, simplifying complex equations, or making random guesses without a strategy do not capture the essence of what estimation accomplishes in mathematical problem-solving, nor do they contribute to the practical and strategic application of mathematical reasoning.