Front-end estimation - Math Seventh Grade

Identify the leftmost digit of each number in the calculation.
Ignore all the other digits to the right of the leftmost digit.
Add or subtract the leftmost digits to get the estimated result.

Let's look at an example to illustrate front-end estimation:Suppose you want to estimate the sum of 356 and 789 using front-end estimation.

The leftmost digit of 356 is 3, and the leftmost digit of 789 is 7.
Ignore all the other digits to the right of the leftmost digit.
Add the leftmost digits: 3 + 7 = 10.

So, using front-end estimation, the estimated sum of 356 and 789 is 1000.Front-end estimation is a quick and handy method for getting a rough idea of the result of a calculation without having to perform the exact arithmetic. However, it's important to note that front-end estimation may not always give a precise estimate, especially when dealing with numbers that are close in value.Study Guide for Front-End Estimation:

Identify the leftmost digit of each number in the calculation.
Ignore all the other digits to the right of the leftmost digit.
Add or subtract the leftmost digits to get the estimated result.
Practice estimating the sums and differences of numbers using front-end estimation.
Compare the estimated results with the actual results to gauge the accuracy of front-end estimation.