Number Theory Challenge: Identifying Prime Numbers

Question

Which of the numbers is a prime number?

Video Solution

Step-by-Step Solution

To determine which number is a prime number, we must individually verify each of the options provided.

  • Check 57 57 :
    • Divisibility by 2: 5757 is odd, so not divisible.
    • Divisibility by 3: Sum of digits 5+7=125 + 7 = 12, divisible by 3, hence 57 is divisible by 3.
    • Conclusion: 57 57 is not a prime number.
  • Check 58 58 :
    • Divisibility by 2: 58 58 is even, hence divisible by 2.
    • Conclusion: 58 58 is not a prime number.
  • Check 55 55 :
    • Divisibility by 2: 5555 is odd, not divisible by 2.
    • Divisibility by 3: Sum of digits 5+5=105 + 5 = 10, not divisible by 3.
    • Divisibility by 5: Ends with 5, divisible by 5.
    • Conclusion: 55 55 is not a prime number.
  • Check 60 60 :
    • Divisibility by 2: 6060 is even, hence divisible by 2.
    • Conclusion: 60 60 is not a prime number.

After evaluating all options, none of the provided numbers is a prime number. It appears there may be a misunderstanding in the problem or typo, as no addtional information is given to explain an alternative solution.

Thus, none of the above numbers are prime, and we should conclude there is either a mistake in the given problem or choices.

Answer

57 57