Simplying (Reducing) Fractions with Divisibility Rules

Using Divisibility Rules helps you when reducing fractions to their simplest form! Remember: to reduce a fraction, you have to divide the numerator and denominator by the same number.

Divisibility Rules	Example
A number is divisible by 2  if the last digit is 0, 2, 4, 6 or 8.	168 is divisible by 2 since the last digit is 8.
A number is divisible by 3  if the sum of the digits is divisible by 3.	168 is divisible by 3 since the sum of the digits is 15 (1+6+8=15), and 15 is divisible by 3.
A number is divisible by 4  if the number formed by the last two digits is divisible by 4.	316 is divisible by 4 since 16 is divisible by 4.
A number is divisible by 5  if the last digit is either 0 or 5.	195 is divisible by 5 since the last digit is 5.
A number is divisible by 6  if it is divisible by 2 AND it is divisible by 3.	168 is divisible by 6 since it is divisible by 2 AND it is divisible by 3.
A number is divisible by 8  if the number formed by the last three digits is divisible by 8.	7,120 is divisible by 8 since 120 is divisible by 8.
A number is divisible by 9  if the sum of the digits is divisible by 9.	549 is divisible by 9 since the sum of the digits is 18 (5+4+9=18), and 18 is divisible by 9.
A number is divisible by 10  if the last digit is 0.	1,470 is divisible by 10 since the last digit is 0.