Four basic operations of arithmetic.
We cannot live a day without numerals. Numbers and numerals are everywhere. On this page you see number names. They are zero, one, two, three, four and so on. And here are the numerals: 0, 1, 2, 3, 4 and so on. In a numeration system, numerals are used to represent numbers, and the numerals are grouped in a special way. The numbers used in our numeration system are called digits.
In our Hindu-Arabic system we use only ten digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 to represent any number. We use the same ten digits over and over again in a place-value system whose base is ten. These digits may be used in various combinations. Thus 1, 2, and 3 are used to write, 123, 132, 213 and so on. One and the same number could be represented in various ways. For example, take number 3. It can be represented as 2 + 1, 4 - 1 and so on.
A very simple way to say that each of the numerals names the same number is to write an equation -a mathematical sentence that has an equal sign (=) between them. For example, 3 + 4 = 5 + 2, or 3 – 1 = 6 - 4. The + is a plus sign. The - is a minus sign. We say three plus six equals five plus four, or three minus 1 is equal to six minus four. Another example of an equation is 3 + 5 = 8. In this equation three is an addend. Five is also an addend. Eight is the sum. We add three and five and we get eight.
There are four basic operations of arithmetic that you all know of. They are addition, subtraction, multiplication and division. In arithmetic an operation is a way of thinking about two numbers and getting one number. As you remember from the above in the operation of addition the two numbers with which you work are called addends or summands and the number that you get as a result of this operation is the sum. In subtraction again you use two numbers. In the equation 7 - 2 = 5 seven is the minuend and two is the substrahend. As a result of this operation you get the difference. We may say that subtraction is the inverse operation of addition since 5 + 2 = 7 and 7 - 2 = 5.
The same might be said about multiplication and division, which are also inverse operations. In multiplication there is a number that must be multiplied. It is the multiplicand. There is also a multiplier. If we multiply the multiplicand by the multiplier we shall get the product as a result. When two or more numbers are multiplied, each of them is called a factor. For example, in the expression 5 x 2 (five multiplied by two), the 5 and the 2 will be factors. The multiplicand and the multiplier are names for factors.
In the operation of division there is a number that is divided and it is called the dividend; the number by which we divide is called the divisor. As a result of the operation of division we shall get the quotient. In some cases the divisor is not contained a whole number of times in the dividend. For example, if you divide 10 by 3 you will get a part of the dividend left over. This part is called the remainder. In our case it will be 1.
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