Rounding and estimating
This lesson about rounding and estimating will show you some of the most common methods of estimation.
Some calculations require an exact answer. Pretend that you buy some groceries from the supermarket
You give the cashier 20 dollars for a purchase of 16.87. An exact answer is important here so you get back the change that you deserve
However, for other situations an estimate is sufficient unless you really want to be picky about it
For example, suppose you lost a certain amount of pounds over the course of a year, you could be satisfied with an estimate
2.4, 2.5, 2.6, 2.3, 2.45, 2.60, 2.41, 2.35, 2.56, 2.49
Cluster estimation may help you see that you lost approximately 2.5 × 10 pounds or 25 pounds
Rounding whole numbers
Learning to round whole numbers is fundamental. This is where all your studies stat.Make sure you got a good understanding of this lesson
before learning anything else. Take your time. We are not in a race here!
Estimating a sum
After you have mastered the lesson about rounding whole numbers, your next stop is right here. This lesson will show you how you can use rounding to the
nearest ten, or hundred to get the best estimate when trying to estimate a sum.
Front end estimation
Next, front end estimation is explored, which can be used to estimate product and division. Unlike estimating a sum, which may try to estimate
by rounding to different places, front end estimation only round and add the numbers in the leftmost place.
You must explore this type of estimating numbers!
Compatible numbers
Finally, compatible will take estimation to a whole new level.If you have no clue what compatible numbers are, this is the time to learn what they are and
how they are used to get good estimate for multiplication and division.
Cluster estimation
Learn how to use cluster estimation to estimate sums and products.
Rounding and estimating quiz. See how well you understand the concepts on this page.