Addition, subtraction, multiplication and division are the basic four operations, and the symbols are "+-×" in turn. Without parentheses, the operation order is multiplication and division first, then addition and subtraction.
1, multiplication, "×" is the multiplication sign, the numbers before and after the multiplication sign are called factors, "=" is the equal sign, and the numbers after the equal sign are called products.
2. Law of division
How many digits is the divisor? Look at the first few digits of the divisor first. If the first few are not enough, look at one more. Except for the one to which they belong, all the vendors will write on it, which is not enough for the quotient of one and zero. The remainder is less than the divisor. If the quotient is decimal, the decimal point of the quotient should be aligned with that of the dividend. If the divisor is a decimal, it must be divided into integers and then calculated.
3. Addition, "+"is a plus sign, the numbers before and after the plus sign are addends, "=" is an equal sign, and the numbers after the equal sign are sums.
4, subtraction, "-"is the negative sign, the minus sign is preceded by the minuend, followed by the minuend, "=" is the equal sign, and the number after the equal sign is the difference.