Divisibility Rule of 393

The divisibility rule for 393 is a method by which we can find out if a number is divisible by 393 or not without using the division method.

Check whether 786 is divisible by 393 with the divisibility rule.  

Step 1: Multiply the last digit of the number by 2, here in 786, 6 is the last digit multiply it by 2. 6 × 2 = 12 

Step 2: Subtract the result from Step 1 from the remaining values but do not include the last digit. i.e., 78 - 12 = 66.

Step 3: Since 66 is not a multiple of 393, the number is not divisible by 393. If the result from step 2 is a multiple of 393, then the number is divisible by 393.

Learning the divisibility rule will help kids master division. Let’s learn a few tips and tricks for the divisibility rule of 393. 

• Know the multiples of 393:  Memorize the multiples of 393 to quickly check divisibility. If the result from the subtraction is a multiple of 393, then the number is divisible by 393. 
   
• Use the negative numbers:  If the result we get after the subtraction is negative, we will ignore the symbol and consider it as positive for checking the divisibility of a number.
   
• Repeat the process for large numbers:  Students should keep repeating the divisibility process until they reach a small number that is divisible by 393.
  
  For example: Check if 1572 is divisible by 393 using the divisibility test.  Multiply the last digit by 2, i.e., 2 × 2 = 4.  
  
  Subtract the remaining digits excluding the last digit by 4, 157 - 4 = 153.  Still, 153 is a large number, hence we repeat the process again: multiply the last digit by 2, 3 × 2 = 6.  
  
  Now, subtracting 6 from the remaining numbers excluding the last digit, 15 - 6 = 9.  Since 9 is not a multiple of 393, 1572 is not divisible by 393.
   
• Use the division method to verify: Students can use the division method as a way to verify and cross-check their results. This will help them verify and also learn.

• Divisibility rule: A set of rules used to find out whether a number is divisible by another number or not.
   
• Multiples: The results we get after multiplying a number by an integer. For example, multiples of 393 are 393, 786, 1179, etc.
   
• Integers: Numbers that include all whole numbers, negative numbers, and zero.
   
• Subtraction: The process of finding the difference between two numbers by reducing one number from another.
   
• Verification: The process of using an alternative method, such as division, to confirm the result obtained from the divisibility rule.