Question

put a check by all the prime numbers.
2
5
7
17
21
26
none of the above

Explanation:

Step1: Recall prime number definition

A prime number is a number greater than 1 that has no positive divisors other than 1 and itself.

Step2: Check each number

• 2: Divisors are 1 and 2. Prime.
• 5: Divisors are 1 and 5. Prime.
• 7: Divisors are 1 and 7. Prime.
• 17: Divisors are 1 and 17. Prime.
• 21: Divisors are 1, 3, 7, 21. Not prime.
• 26: Divisors are 1, 2, 13, 26. Not prime.
• "None of the above" is incorrect as there are primes.

Answer:

The prime numbers are 2, 5, 7, 17. So the boxes to check are next to 2, 5, 7, and 17.