There are two integers between 20 and 30 that are prime.
Understanding Prime Numbers
A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. For example, 7 is a prime number because its only positive divisors are 1 and 7. Numbers like 6 are not prime because they have divisors other than 1 and 6 (e.g., 2 and 3).
Identifying Prime Numbers Between 20 and 30
To find the prime numbers within a specific range, we examine each integer and determine if it meets the definition of a prime number. The integers between 20 and 30 are:
- 21 (divisible by 3, 7) - Not prime
- 22 (divisible by 2, 11) - Not prime
- 23 (only divisible by 1 and 23) - Prime
- 24 (divisible by 2, 3, 4, 6, 8, 12) - Not prime
- 25 (divisible by 5) - Not prime
- 26 (divisible by 2, 13) - Not prime
- 27 (divisible by 3, 9) - Not prime
- 28 (divisible by 2, 4, 7, 14) - Not prime
- 29 (only divisible by 1 and 29) - Prime
As confirmed by BYJU'S, the prime numbers between 20 and 30 are specifically identified as 23 and 29.
Prime Numbers Chart (1 to 40)
To provide broader context, here's a segment of a prime numbers chart, illustrating primes within different tens ranges:
| Range | Prime Numbers |
|---|---|
| Prime numbers between 1 and 10 | 2, 3, 5, 7 |
| Prime numbers between 10 and 20 | 11, 13, 17, 19 |
| Prime numbers between 20 and 30 | 23, 29 |
| Prime numbers between 30 and 40 | 31, 37 |
This table, derived from reliable sources like BYJU'S, clearly shows that 23 and 29 are the only prime numbers in the specified range.
Conclusion
Based on the definition of prime numbers and readily available prime number charts, there are exactly two integers between 20 and 30 that are prime: 23 and 29.
