Factors, multiples, prime and composite: printable worksheets

Find factor pairs and multiples, and tell whether a number from 1 to 100 is prime or composite.

Sample worksheet

The first 4 problems of a real worksheet, made the way the builder makes it. Open it in the builder to change the number of problems, the difficulty and the layout, then print.

Is 73 prime or composite?

prime
composite

Is 78 prime or composite?

prime
composite

Is 1 prime, composite, or neither?

prime
composite
neither

Is 57 prime or composite?

prime
composite

Show answers

1.prime

2.composite

3.neither

4.composite

What students practise

I can find all the factor pairs of a number and tell if it is prime or composite.

Students find every factor pair of a whole number to one hundred, list multiples, and tell whether a number is prime or composite.

Key words

factor: a number that divides another number with nothing left over
factor pair: two factors that multiply to make the number
multiple: the product of a number and a whole number, found by skip counting
common multiple: a number that is a multiple of two different numbers
prime: a number with exactly two factors: 1 and itself
composite: a number with more than two factors
neither: 1 has only one factor, so it is not prime and not composite

Common mistakes

Thinks every odd number is prime, such as 51 or 91.
Calls 1 a prime number.
Stops before the last pair, or lists the middle factor of 36 twice.
Mixes up factors and multiples, such as calling 21 a factor of 7.

Standards

Common Core State Standards this worksheet practises.

4.OA.B.4: Find all factor pairs for a whole number in the range 1-100. Recognize that a whole number is a multiple of each of its factors. Determine whether a given whole number in the range 1-100 is a multiple of a given one-digit number. Determine whether a given whole number in the range 1-100 is prime or composite. (unverified)

Before this: Multiplication concepts (Grade 3)
Next: Multi-digit multiplication (Grade 4)