Answer :
When you estimate your answer, you get a roundabout number for it.
When you do your calculations, if your answer is much different from your estimate, that tells you that you need to double check your work.
When you do your calculations, if your answer is much different from your estimate, that tells you that you need to double check your work.
The correct answer is:
Make your estimate first. Once you have completed your exact calculations, compare your answer to your estimate. If your answer is close to your estimate, then your answer can be considered reasonable. If, however, the calculations and the estimate are very different, one or both may be incorrect.
