Many people are interested in how to round numbers. This need often arises in people who associate their lives with bookkeeping or other activities where calculations are required. Rounding can be made up to whole, tenths and so on. And you need to know how to do it correctly so that the calculations are more or less accurate.
And what is a round number in general? This is one that ends with 0 (for the most part). In everyday life, the ability to round numbers greatly facilitates shopping. Standing at the checkout, you can approximately estimate the total cost of purchases, compare how much a kilogram of the same product costs in packages of various weights. With numbers reduced to a convenient form, it is easier to make verbal calculations without resorting to a calculator.
Why are numbers rounded up?
A person is inclined to round off any figures in those cases when it is necessary to perform more simplified operations. For example, a melon weighs 3.150 kilograms. When a person tells his friends about how many grams a southern fetus has, he may pass for a not-so-interesting interlocutor. Phrases like “So I bought a three-kilogram melon” sound much more concise without going into any unnecessary details.
Interestingly, even in science there is no need to always deal with the most accurate numbers. And if we are talking about periodic infinite fractions, which have the form 3.33333333 ... 3, then this becomes impossible. Therefore, the most logical option would be to normally round them. As a rule, the result after this is slightly distorted. So how to round numbers?
Some important rules when rounding numbers
So, if you want to round a number, is it important to understand the basic principles of rounding? This is an operation to change the decimal fraction, aimed at reducing the number of decimal places. To carry out this action, you need to know several important rules:
- If the number of the desired discharge is in the range of 5-9, rounding is carried out in a larger direction.
- If the number of the required discharge is in the range of 1-4, rounding is performed in a smaller direction.
For example, we have the number 59. We need to round it. To do this, you need to take the number 9 and add one to it to get 60. Here's the answer to the question of how to round numbers. And now we will consider special cases. Actually, we figured out how to round a number to tens using this example. Now it remains only to use this knowledge in practice.
How to round a number to integers
It often happens that there is a need to round, for example, the number 5.9. This procedure is not difficult. First we need to omit the comma, and before our eyes, when we round off, we see the number 60 already familiar to us. Now we put the comma in its place and we get 6.0. And since zeros in decimal fractions, as a rule, are omitted, we get the number 6 in the end.
A similar operation can be performed with more complex numbers. For example, how to round numbers like 5.49 to integers? It all depends on what goals you set for yourself. In general, according to the rules of mathematics, 5.49 is still not 5.5. Therefore, it cannot be rounded up. But you can round it to 5.5, after which rounding to 6 becomes legal. But such a trick does not always work, so you need to be extremely careful.
How to round numbers after decimal point to tenths?
In principle, the example of correct rounding of the number to tenths has already been considered above, so now it is important to display only the main principle. In fact, everything happens in approximately the same way. If the digit, which is in the second position after the decimal point, is in the range of 5-9, then it is generally removed, and the digit in front of it is increased by one. If less than 5, then this figure is removed, and the previous one remains in its place.
For example, when rounding the number 4.59 to 4.6, the number "9" goes away, and one is added to the five. But when rounding 4.41, the unit is omitted, and the four remain in an unchanged form.
How do marketers use the inability of the mass consumer to round numbers?
It turns out that most of the people in the world have no habit of evaluating the real value of the product, which is actively exploited by marketers. Everyone knows the slogans of stocks like "Buy for only 9.99." Yes, we consciously understand that this is essentially ten dollars. Nevertheless, our brain is designed so that it perceives only the first digit. So the simple operation of bringing the number into a convenient form should become a habit.
Very often rounding allows you to better evaluate intermediate successes, expressed in numerical form. For example, a person began to earn 550 dollars a month. An optimist will say that it is almost 600, a pessimist - that it is a little more than 500. It seems to be a difference, but the brain is more pleased to “see” that the object has achieved something more (or vice versa).
You can give a huge number of examples when the ability to round is incredibly useful. It is important to be creative and, if possible, to load up with unnecessary information. Then success will be immediate.