Prime Numbers Worksheet aims to provide a clear understanding of prime numbers, their properties, and how to identify them. Through the worksheet, learners can practice identifying prime numbers and strengthen their number theory and divisibility skills.
Prime Numbers Questions with Solutions
Question 1: Determine if 29 is a prime number.
Solution:
Check divisibility by numbers from 2 to
\sqrt{29} ≈ 5.39.29 is not divisible by 2, 3, or 5.
Since it has no divisors other than 1 and 29, 29 is a prime number.
Question 2: Is 51 a prime number?
Solution:
Check divisibility by numbers from 2 to
\sqrt{51} ≈ 7.14.51 is divisible by 3 (since 51 ÷ 3 = 17).
Therefore, 51 is not a prime number (it is a composite number).
Question 3: Find all prime numbers less than 20.
Solution:
Start with 2: It is prime.
- 3: Prime (no divisors other than 1 and 3).
- 4: Not prime (divisible by 2).
- 5: Prime (no divisors other than 1 and 5).
- 6: Not prime (divisible by 2).
Continue this way for numbers up to 20.
Prime numbers less than 20 are: 2, 3, 5, 7, 11, 13, 17, 19.
Question 4: Is 91 a prime number?
Solution:
Check divisibility by numbers from 2 to
\sqrt{91} ≈9.53.91 is divisible by 7 (since 91÷7=13).
Therefore, 91 is not a prime number.
Question 5: Determine if 83 is a prime number.
Solution:
Check divisibility by numbers from 2 to
\sqrt{83} ≈9.11.83 is not divisible by any of 2, 3, 5, 7.
Therefore, 83 is a prime number.
Prime Numbers Worksheet with Answer Key
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