One method in reducing fractions is to find a common factor that can be divided evenly into both the numerator (top number) and the denominator (bottom number).

A quick way to determine a common factor is to consider the divisibility rules for 2, 3, 5, and 10.

****A number is divisible by 2 IF the last digit of the number is an even number. That is, if the last digit is a 0, 2, 4, 6, or 8.**

Positive example: 346 is divisible by 2 because the last digit 6 is an even number.

Negative example: 467 is not divisible by 2 because the last digit 7 is NOT an even number.

****A number is divisible by 3 if the sum of the digits is divisible by 3.**

Positive example: 246 is divisible by 3 because 2+4+6= 12 and 12 is divisible by 3.

Negative example: 211 is NOT divisible by 3 because 2+1+1= 4 and 4 is not divisible by 3.

****A number is divisible by 5 if the last digit is a “0” or “5”.
**

Positive example: 12,435 is divisible by 5 because the last digit is a “5”.

Negative example: 11,231 is NOT divisible by 5 because the last digit is a 1, not a “0” or “5”.

**** A number is divisible by 10 if the last digit is a “0”.**

Positive example: 12, 340 is divisible by 10 because the last digit is a “0”.

Negative example: 986 is NOT divisible by 10 because the last digit is a 6, not a “0”.

**Remember, when you reduce fractions….. you use a form of 1. That means that both the numerator and denominator must be divisible by the SAME number.**

Worksheets and answer keys are PDF downloads.

Example:

4/6 can be divided by 2/2 and reduced to 2/3.

Reducing Fractions Worksheet 1

Reducing Fractions Worksheet 1- Answer Key

Reducing Fractions- Answer Key