Divisibility Rule of 665

The divisibility rule for 665 is a method by which we can find out if a number is divisible by 665 or not without using the division method.

Check whether 1995 is divisible by 665 with the divisibility rule.

Step 1: Ensure the number is divisible by both 5 and 133, as 665 = 5 × 133. First, check divisibility by 5. Since 1995 ends in 5, it is divisible by 5.

Step 2: Now, check for divisibility by 133. Divide the number excluding the last digit by 133. Here, divide 199 by 133. Since 199 is greater than 133, subtract 133 from 199 to check if it's divisible by 133. 199 - 133 = 66.

Step 3: Since 66 is not divisible by 133, 1995 is not divisible by 665.

Learning divisibility rules will help kids master division. Let’s learn a few tips and tricks for the divisibility rule of 665.

• Know the multiples of 665: Memorize the multiples of 665 (665, 1330, 1995, 2660, etc.) to quickly check divisibility. If the result from subtraction or division is a multiple of 665, the number is divisible by 665.
   
• Use divisibility rules of factors: Since 665 = 5 × 133, check divisibility by 5 and 133 separately. If both conditions are met, the number is divisible by 665.
   
• Repeat the process for large numbers: For large numbers, repeat the divisibility checks until you reach a smaller, more manageable number.
   
• Use the division method to verify: Students can use the division method to verify and cross-check their results. This will help them verify and also learn.

• Divisibility rule: The set of rules used to find out whether a number is divisible by another number or not. For example, a number is divisible by 5 if it ends in 0 or 5.
   
• Multiples: Multiples are the results we get after multiplying a number by an integer. For example, the multiples of 665 are 665, 1330, 1995, etc.
   
• Factors: Factors are numbers that divide another number completely without leaving a remainder. In this context, 5 and 133 are factors of 665.
   
• Subtraction: Subtraction is a process of finding out the difference between two numbers by reducing one number from another.
   
• Integer: An integer is any whole number, positive or negative, including zero.