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What are prime numbers? What are composite numbers? Who are prime numbers and composite numbers in 1-20?
A prime number is one which can only be divided by one and itself, that is to say, a composite number is one which has divisors besides one and itself. For example, 1235711131719 is a prime number and the rest is a composite number
What are prime numbers, composite numbers?
Prime number
Prime number is also called prime number. It refers to the number in a natural number greater than 1 which can not be divided by other natural numbers except 1 and the integer itself. In other words, a natural number with only two positive factors (1 and itself) is a prime number
The smallest prime number is 2, which is also the only even prime number. The first prime numbers are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29 and 31
Total number
Numbers larger than 1 but not prime are called composite numbers
1 and 0 are neither prime nor composite
A number that can be divisible by other numbers in addition to 1 and the number itself
For example, 6 can be divided by 1 and 6, and also by 2 and 3
4,6,8,10,12,14,16,18,20,22,24,26,28,30.
What are the definitions of prime numbers and composite numbers?
Ask for a concise answer
Prime number (also known as prime number, pure number)
For example, 2,3,5,7 (within 10) are prime numbers, while 4,6,8,9 are not. The latter is called composite number or composite number. Composite number is a natural number which can be divided by other integers except 1 and itself
RELATED INFORMATIONS
- 1. What do prime numbers and composite numbers mean?
- 2. What is the meaning of prime number and composite number?
- 3. Write two numbers as required, so that their greatest common factor is 1. Prime number () and composite number. Prime number () and prime number. Composite number () and composite number
- 4. Write numbers as required so that their greatest common factor is 1. Both numbers are prime numbers: () and (), a prime number and a composite number: () and () Write numbers as required so that their greatest common factor is 1 Both numbers are prime numbers: () and () A prime number and a composite number: () and () Both are composite numbers: () and () An even number and an odd number: () and () A prime number and an odd number: () and ()
- 5. The product of a prime number and a composite number is 48?
- 6. Multiplication of two prime numbers, product number. Right or wrong?
- 7. The smallest prime number is______ The smallest sum is______ The product of them is______ ．
- 8. The product of two prime numbers must be______ ．
- 9. Are all composite numbers made up of two prime numbers?
- 10. What is the quotient of the smallest prime half plus the smallest sum divided by 8 / 9?
- 11. A number () is called prime. A number () is called composite
- 12. What is the sum of the smallest composite number and the number that is neither prime nor composite?
- 13. For a three digit number, the number on the hundred is a composite number and an odd number, the number on the ten is a prime number and an even number, and the number on the one digit is neither a prime nor a composite number What are the three digits?
- 14. Natural numbers (except 0) are either prime numbers or composite numbers______ (judge right or wrong)
- 15. What are prime numbers, composite numbers and natural numbers
- 16. A natural number, if not prime, must be a composite number______ (judge right or wrong)
- 17. 1、 The divisor of 1.54 is (), in which the odd number is (), the combined number is (), the prime number is (), and the even number is () 2. "2 / 3 of 12 chickens", here () is regarded as unit '1'. 2 / 3 means that the unit '1' is divided into () parts averagely, taking () parts, and "2 / 3 of 12 chickens" is () chickens 3. Three continuous natural numbers, the middle one is a, and the other two are (), () The greatest common divisor of 4.20 and 24 is () and the least common multiple is () In 5.1 and 4 / 5, there are () 1 / 5, and 8 1 / 4 are () 6. The unit of fraction is 1 / 4. The sum of all true fractions is () 7. Fill in the appropriate unit name or number in brackets 86 CC = 0.086 () 1.8 m3 = () l 8. The maximum three digits divisible by 2, 5 and 3 at the same time are () 9. Fill in a number in 324 () so that the number has a factor of 2, a multiple of 5, and can be divided by 3 2、 Judgment questions 1. If a number can be divided by 15, it must be divided by 3 and 5 at the same time 2. The fraction whose numerator is less than the denominator is true, and the fraction whose numerator is greater than the denominator is false 3. Multiply or divide the numerator and denominator of a fraction by the same number (except zero), and the unit of the fraction remains unchanged 4. The volume of a 400 cubic centimeter thermos cup should be smaller than 400 ml 5. Both a and B are natural numbers. If a △ B = 7, then the greatest common factor of a and B is 7 6. Fractions with the same denominator can be added or subtracted directly because their fractional units are the same 3、 Practical questions 2. Xiaohong's family bought a new goldfish tank with a side length of 4 decimeters on the bottom and 30 liters of water. How deep is it? 3. Two cuboids of equal volume are stacked to form a cuboid with a height of 12 cm. What is the surface area of the cuboid? What is the surface area of the newly stacked cuboid?
- 18. Which of the following numbers are prime numbers? Which are composite numbers? Please decompose the composite numbers into prime factors: 23, 32, 47, 65, 71, 78, 93 Let's say that 2 is equal to 1 × 2
- 19. Is 209 prime or composite? If it is a composite number, please decompose it into prime factors
- 20. The sum of two prime numbers is not only a multiple of 11, but also an even number less than 50