Table of Contents
Table of Contents
- Making Estimations
- Rounding off Numbers to Nearest 10
- Summary
- What’s Next?
In our previous segment, we were introduced to the concept of estimation. In this segment, we will learn how estimations are made by rounding off numbers.
How are estimations made?
Estimation solely depends on what the number that has to be estimated represents.
For example, the number 89 can be estimated to be 80 in one case, and 100 in another. Let us see how.
Let us imagine that Ben spends 89 Rupees on a commodity. If he has to report to his parents about his spending then approximating the amount spent to 90 Rupees would be a better option.
But if Ben’s parents have roughly asked him about his spendings then rounding off the amount to 100 would also be a rational estimate.
Thus, we can say that the estimate can vary depending on the situation. Let us now learn how to estimate values for a given number.
How to make estimations to the nearest 10s?
Nearest ten means nearest multiples of ten. So, in this method, we round off numbers to 10,
20, 30, … 90, 100, 110, … 200, 210, 220 and so on.
While rounding off numbers to nearest 10, there can be three cases:
(i) The number has a digit lesser than 5 in its units place
Here the given number is rounded off to a number to the nearest 10, lesser than the given number.
