Flashcard on Prime Numbers

Front

What is a prime number?

Back

A prime number is a number that has exactly two factors: 1 and itself.

Front

Which set contains only prime numbers?

Back

The set {2, 3, 5, 7} contains only prime numbers.

Front

What is the next prime number after 7?

Back

The next prime number after 7 is 11.

Front

How can you tell if a number is NOT prime?

Back

A number is NOT prime if it has more than two factors.

Front

Which is the smallest two-digit prime number?

Back

The smallest two-digit prime number is 11.

Front

List the first five prime numbers.

Back

The first five prime numbers are 2, 3, 5, 7, and 11.

Front

Is 1 a prime number? Why or why not?

Back

No, 1 is not a prime number because it has only one factor.

Front

What is the only even prime number?

Back

The only even prime number is 2.

Front

Can prime numbers be negative?

Back

No, prime numbers are defined only for positive integers.

Front

What is the sum of the first three prime numbers?

Back

The sum of the first three prime numbers (2, 3, and 5) is 10.