我们为什么使用数字?
数字是社会世界中金融、专业以及社会领域中使用的数学数字。数字中的位数和位值以及数字系统的基数决定了数字的值。数字用于各种数学运算,如加法、减法、乘法、除法、百分比等,这些运算用于我们的日常业务和交易活动。
Numbers are the mathematical figures or values applicable for counting, measuring, and other arithmetic calculations. Some examples of numbers are integers, whole numbers, natural numbers, rational and irrational numbers, etc.
数字系统是一种将数字表达为不同形式的标准化方法,即数字和文字。它包括不同类型的数,例如素数、奇数、偶数、有理数、整数等。这些数可以根据所使用的数系以形式表示。
数系包括不同类型的数,例如质数、奇数、偶数、有理数、整数等。这些数可以相应地以数字和文字的形式表示。
例如,40、65等以数字形式表示的数字,也可以写成40、65。
表示数字的基本系统称为数字系统。它是数字表示的标准化方法,其中数字以算术和代数结构表示。
数字类型
有不同类型的数字按数字系统分类。类型描述如下:
- 自然数:自然数从 1 到无穷大。它们是用“N”表示的正计数数。这是我们通常用于计数的数字。自然数集合可以表示为 N = {1,2,3,4,5,6,7,………………}
- 整数:整数从零到无穷大。整数不包括分数或小数。整数集由“ W”表示。该集合可以表示为 W={0,1,2,3,4,5,………………}
- 有理数:有理数是可以表示为两个整数之比的数。它包括所有整数,可以用分数或小数表示,用“Q”表示。
- 无理数:无理数是不能用分数或整数比表示的数字。它可以写成小数,小数点后有无穷无尽的不重复数字。它们由“P”表示。
- 整数:整数是一组数字,包括所有正数、零以及从负无穷到正无穷的所有负数。该集合不包括分数和小数。整数集由“Z”表示。示例:Z={…………..,-5.-4,-3,-2,-1,0,1,2,3,4,5,………….}
- 十进制数:任何由小数点组成的数值都是十进制数。可以表示为2.5、0.567等。
- 实数:不包括任何虚数并且是所有正整数、负整数、分数和十进制值的组成部分的数字集合是实数。它通常用“R”表示。
- 复数:它们是一组数字,其中包括虚数是复数。它可以表示为 a+bi,其中“a”和“b”是实数。它用“C”表示。
我们为什么使用数字?
回答:
We use numbers in date, time, year and weather. We also use numbers in our daily life like school and work, counting money, measurements, phone numbers, password on our phone , locks, reading, page numbers, and TV channels.
Engineers use number according top specify fields like calculation to construct building and roads and Doctors use it for their patient blood counts and medicines.
- Some one has to Call a member of a family or a friend using mobile phone.
- Calculating your daily budget, expenses for your food, transportation
- The work which involves the idea of proportion and percentage.
- In shopping like Weighing fruits, vegetables, meat, chicken, and others in market.
- Using numbers of elevators to go places or floors in the building.
- Look at the price of discounted items in a shopping mall.
- Change the number of channels of your favorite TV shows.
- The time you spent on work or school.
- Calculating the interest you gained on your business.
数系包括不同类型的数,例如质数、奇数、偶数、有理数、整数等。这些数可以相应地以数字和文字的形式表示。
For example, the numbers like 40 and 65 expressed in the form of figures can also be written as forty and sixty-five.
The elementary system to express numbers is called a number system. It is the standardized method for the representation of numerals in which numbers are represented in arithmetic and algebraic structure.
示例问题
问题一:两个最小的自然数相加?
解决方案:
1, 2 are the smallest natural numbers
So 1 + 2 = 3 also a natural number
问题2:一个数乘以7乘以5,结果是40。求这个数。
解决方案:
Lets assume the number is x
According to question
7 x + 5 = 40
Now we can write as
7 x = 40 – 5
and 7x = 35
x = 35/7
x = 5
So the number is 5.
问题 3:在给定的方程 4a – 50 = 6 中找到 a 的值。
解决方案:
According to the equation,
=> 4a – 50 = 6
=> 4a = 50 + 6
=> 4a = 56
=> a = 56/4
=> a = 16
Therefore, the value of a is 16.
问题 4:求 100 和 40 之和,然后减去 30?
解决方案:
Here, the sum of 100 and 40 by using the addition operation.
Sum = 100 + 40 = 140
Now, as per the question, subtract 20 from the sum,
140 – 30 = 110
Therefore, 110 is the final answer