最小的三位数质数是多少?
表示和处理数字的方法称为数字系统。数字系统是一种表示数字的书写系统。它是用于通过使用数字或其他符号来表示给定集合的数字的数学符号。它允许我们进行算术运算,例如除法、乘法、加法、减法。一些重要的数字系统如下, 十进制数系统、二进制数系统、八进制数系统和十六进制数系统。
让我们详细了解所有这些数字系统。
十进制数系统
十进制数字系统由十位数字组成,即从0到9。十进制数字系统的基数是10。这些数字可以用来表示或表达任何数值。例如,十进制数 153 由个位数字 3、十位数字 5 和百位数字 1 组成,可以表示为:
(1 × 10 2 ) + (5 × 10 1 ) + (3 × 100 0 )
= (1 × 100) + (5 × 10) + (3 × 1) { 其中,100 = 1}
= 100 + 50 + 3
= 153
质数
在数字系统中,质数是那些只有两个因子的数字,即 1 和数字本身。换句话说,质数是那些能被 1 和数字本身整除的数字。
- 一个素数应该正好包含两个因子。
- 素数应该能被 1 和数字本身整除。
让我们假设 p 是一个素数,那么 p 只有 2 个因子,即 1 和 p 本身。任何不跟随它的数字都称为合数。例如 8 的因子是 1、2、4 和 8,它们总共是四个因子。但是5的因数是1和5本身,完全是两个因数。因此,5 是素数,但 8 不是素数,而是合数。前十个自然素数是 – 2, 3, 5, 7, 11, 13, 17, 19, 23, 29
下面是从 1 到 100 的素数列表,
注1 是非素数,因为根据定义,素数应该只包含两个因数,而 1 只有一个因数。所以1不是素数。
1到100之间的质数列表
素数是只有两个因子的数字,即 1 和数字本身。让我们看看一些介于 1 到 100 之间的素数,以及它们的因数。
2 = (1, 2), 3 = (1, 3), 5 = (1, 5), 7 = (1, 7), 11 = (1, 11), 13 = (1, 13), 17 = (1, 17), 19 = (1, 19), 23 = (1, 23), 29 = (1, 29), 31 = (1, 31), 37 = (1, 37), 41 = (1 , 41), 43 = (1, 43), 53 = (1, 53), 59 = (1, 59), 61 = (1, 61), 67 = (1, 67), 71 = (1, 71 ), 73 = (1, 73), 79 = (1, 79), 83 = (1, 83), 89 = (1, 89), 97 = (1, 97)。
最小的三位数质数是多少?
数字系统中最小的 3 位数字是 100,因为如果我们从数字 (100) 中减去 -1,它就会变成 99,这是一个 2 位数字。因此,100 是数字系统中最小的 3 位数字。 100 的因数是 = 1、2、4、5、10、20、25、50 和 100。
素数只有两个因数,即它可以被 1 或数字本身整除。 100 不满足素数的所有条件,这就是为什么 100 不是素数。让我们将值 (100) 增加 +1,然后它变为 101。101 的因子是 = 1 和 101。素数只有两个因子,即它可以被 1 或数字本身整除。 101满足质数的所有条件。所以,101是一个素数。
因此,101 是数字系统中最小的 3 位素数。
示例问题
问题1:最大的3位质数是多少?
解决方案 :
First, find the largest 3 digit number in the number system. The largest 3 digit number in the number system is 999 because if +1 is added to the number (999) it becomes 1000 which is a 4 digit number. So 999 is the largest 3 digit number in the number system.
Now check all the factors of the numbers in the reverse format and stop when the number has only 2 factors.
- Factors of 999 are = 1, 3, 9, 27, 37, 111, 333, 999.
- Factors of 998 are = 1, 2, 499, 998
- Factors of 997 are = 1, 997
A prime number has only two factors i.e. it is divisible by either 1 or by the number itself. As 999 has 8 factors and it doesn’t satisfy all the conditions of a prime number that’s why 999 is not a prime number.
Similarly, 998 has more than 2 factors and it doesn’t satisfy all the conditions of a prime number. So 998 is not a prime number, but 997 has only 2 factors that satisfy all the conditions of a prime number. So 997 is a prime number.
Therefore, 997 is the largest 3-digit prime number in the number system.
问题2:最小的2位素数是多少?
解决方案:
The smallest 2 digit number in the number system is 10 because if we subtract -1 from the number (10) it becomes 9 which is a 1 digit number. So 10 is the smallest 2 digit number in the number system. Factors of 10 are = 1, 2, 5, 10.
A prime number has only two factors i.e. it is divisible by either 1 or by the number itself. 10 doesn’t satisfy all the conditions of a prime number that’s why10 is not a prime number. Let’s increase the value (10) by +1 then it becomes 11. Factors of 11 are = 1 and 11
A prime number has only two factors i.e. it is divisible by either 1 or by the number itself. 101 satisfy all the conditions of a prime number. So, 11 is a prime number.
Therefore, 11 is the smallest 2-digit prime number in the number system.
问题3:最大的2位素数是多少?
解决方案 :
First, find the largest 2 digit number in the number system. The largest 2 digit number in the number system is 99 because if +1 is added to the number (99) it becomes 100 which is a 3 digit number. So 99 is the largest 2 digit number in the number system.
Now check all the factors of the numbers in the reverse format and stop when the number has only 2 factors.
- Factors of 99 are = 1, 3, 9, 11, 33, and 99.
- Factors of 98 are = 1, 2, 7, 14, 49, 98.
- Factors of 97 are = 1, 97
It is known that a prime number has only two factors i.e. it is divisible by either 1 or by the number itself, 99 has 6 factors and it doesn’t satisfy all the conditions of a prime number that’s why 99 is not a prime number. Similarly, 98 has more than 2 factors and it doesn’t satisfy all the conditions of a prime number. So 98 is not a prime number, but 97 has only 2 factors that satisfy all the conditions of a prime number. So 97 is a prime number.
Therefore, 97 is the largest 2-digit prime number in the number system.