Divisibility Rule of 47

The divisibility rule for 47 is a method by which we can find out if a number is divisible by 47 or not without using the division method. Check whether 3298 is divisible by 47 with the divisibility rule.
 

Step 1: Double the last digit of the number. Here in 3298, 8 is the last digit, so double it: 8 × 2 = 16.
 

Step 2: Subtract the result from Step 1 from the remaining number excluding the last digit. i.e., 329 – 16 = 313.
 

Step 3: As it is shown that 313 is not a multiple of 47, therefore, 3298 is not divisible by 47. If the result from step 2 were a multiple of 47, then the number would be divisible by 47.
 

Learning the divisibility rule will help kids to master division. Let’s learn a few tips and tricks for the divisibility rule of 47.
 

• Know the multiples of 47: Memorize the multiples of 47 (47, 94, 141, 188, 235, etc.) to quickly check the divisibility. If the result from the subtraction is a multiple of 47, then the number is divisible by 47.
   
• Use the negative numbers: If the result we get after the subtraction is negative, we will ignore the sign 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 clearly divisible by 47.
  
  For example: Check if 4706 is divisible by 47 using the divisibility test. Double the last digit, i.e., 6 × 2 = 12.
  
  Subtract 12 from the remaining numbers, 470 – 12 = 458. Repeat the process: double the last digit of 458, 8 × 2 = 16. Now subtract 16 from 45, 45 – 16 = 29.
  
  Since 29 is not a multiple of 47, 4706 is not divisible by 47.
   
• 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 to verify and also learn.
   

• Divisibility rule: The set of rules used to find out whether a number is divisible by another number without performing division.
   
• Multiples: Multiples are the results we get after multiplying a number by an integer. For example, multiples of 47 are 47, 94, 141, 188, etc.
   
• Integers: Integers are numbers that include all whole numbers, negative numbers, and zero.
   
• Subtraction: Subtraction is the process of finding out the difference between two numbers by reducing one number from another.
   
• Division method: A mathematical process used to divide one number by another to find a quotient.