Divisibility Rule of 15

The divisibility rule for 15 is a method by which we can find out if a number is divisible by 15 or not without using the division method. Check whether 345 is divisible by 15 with the divisibility rule.

Step 1: Check if the number is divisible by 3. Add the digits of the number, 3+4+5=12. Since 12 is divisible by 3, the number passes this part of the test.

Step 2: Check if the number is divisible by 5. Since 345 ends in 5, it is divisible by 5.

Step 3: As the number passes both tests (divisible by both 3 and 5), 345 is divisible by 15. 

Learning the divisibility rule will help kids master division. Let’s learn a few tips and tricks for the divisibility rule of 15.

• Know the multiples of 15: Memorize the multiples of 15 (15, 30, 45, 60, 75, etc.) to quickly check the divisibility. If a number matches one of these multiples, it is divisible by 15.

• Break the rule into parts: Since 15 is the product of 3 and 5, check divisibility by both numbers separately to determine divisibility by 15.

• 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 method used to determine whether one number is divisible by another without performing actual division.

• Multiples: Numbers obtained by multiplying a given number by an integer. For example, multiples of 15 are 15, 30, 45, 60, etc.

• Integers: Whole numbers that include positive numbers, negative numbers, and zero.

• Sum of digits: The total obtained by adding all the digits of a number together.

• Divisible: A number is divisible by another if, after division, the remainder is zero.