Grade 4 Factors & Multiples: Unit Review

Worked examples

Real problems from the practice worksheets, solved one step at a time.

1. Example 1

   How many factors does 26 have?

   1. List the factor pairs of 26: 1 × 26, 2 × 13.
   2. Every number in a pair is a factor, so the factors of 26 are 1, 2, 13, 26.
   3. Count them: 26 has 4 factors. (More than two factors, so 26 is composite.)

   Answer: 4

2. Example 2

   What is the 5th multiple of 10?

   1. The multiples of 10 are what you get when you skip count by 10: 10, 20, 30, 40, 50.
   2. The 5th multiple is 10 × 5 = 50.
   3. So the answer is 50.

   Answer: 50

3. Example 3

   What is the greatest common factor (GCF) of 45 and 56?

   1. The factors of 45 are 1, 3, 5, 9, 15, 45.
   2. The factors of 56 are 1, 2, 4, 7, 8, 14, 28, 56.
   3. The factors they share are 1. The greatest one is 1.
   4. The GCF of 45 and 56 is 1.

   Answer: 1