Prime and Composite Numbers

Math ⇒ Number and Operations

Prime and Composite Numbers starts at 6 and continues till grade 12. QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Prime and Composite Numbers. How you perform is determined by your score and the time you take. When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.

See sample questions for grade 7

Explain why 11 is a prime number.

Explain why 15 is a composite number.

Explain why 2 is considered a prime number.

Explain why 49 is not a prime number.

List all the composite numbers between 1 and 10.

List all the prime numbers between 10 and 20.

What is the definition of a composite number?

What is the difference between a prime number and a composite number?

What is the next prime number after 31?

What is the smallest composite number?

What is the sum of the first three prime numbers?

A student claims that every number ending in 5 is a composite number. Is this claim correct? Justify your answer.

Explain why the number 221 is a composite number and identify its prime factors.

Find the smallest three-digit composite number that is divisible by exactly three different prime numbers.

If a number is divisible by both 3 and 5, can it be a prime number? Explain your answer.