Consider the numbers 13, 16, 27, and 41.
a. Which of these numbers are prime? How do you know?
b. Which of these numbers are composite? How do you know
a. The numbers 13 and 41 are prime numbers. A prime number is a number that is only divisible by 1 and itself. Neither 13 nor 41 have any divisors other than 1 and themselves, so they are prime.
b. The numbers 16 and 27 are composite numbers. A composite number is a number that has divisors other than 1 and itself. Both 16 and 27 have divisors other than 1 and themselves. For example, 16 is divisible by 2, 4, and 8, while 27 is divisible by 3 and 9, among other factors.