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Front End Estimation and Compatible Numbers


Videos, worksheets, stories and songs to help Grade 6 students learn about Front End Estimation and Compatible Numbers.

Front End Estimation (Rounding)

Front End Estimation is a way of estimating the sums, differences or products of numbers by rounding.
We first round each number to its leftmost place values and then perform the operation.
To add 67+ 24
Round each number using front-end estimation and then add
70 + 20 = 90

Front end rounding
This video explains what front end rounding is and how to apply it to a couple of examples. It works like normal rounding except we always round to the largest place value.

Front End Estimation (Truncate)

Another way of Front End Estimation is to truncate each number to its leftmost place values and then perform the operation.

To add 67+ 24
Truncate each number using front-end estimation and then add
60 + 20 = 80

Front End Estimation for Addition.

Using Front end estimation to check that your answer is reasonable.
Use Front End Estimation for Multiplication
Learn to use front end estimation
Sean has three binders of baseball cards, each with 175 cards. About how many basball cards does he have in all?


Compatible Numbers

Compatible numbers are often used when estimating division. Compatible numbers are numbers that are close to the original numbers but they divide evenly into each other.

Describe three estimation strategies: rounding, front-end estimation, and using compatible numbers.
3 Kinds of Estimation
This video looks at Front-End Estimation, Clustering, and using Compatible Numbers. It includes six examples.

Estimating with Whole Numbers
This video explains how to estimate addition, subtraction, multiplication, and division math problems by using rounding and compatible numbers.
Estimation Using Compatible Numbers


Rotate to landscape screen format on a mobile phone or small tablet to use the Mathway widget, a free math problem solver that answers your questions with step-by-step explanations.

You can use the free Mathway calculator and problem solver below to practice Algebra or other math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.

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