Divisibility Rule of 15: Rule, Examples
Divisibility Rule of 15
A number is divisible by 15 if it is divisible by both 3 and 5 at the same time.
1. Divisible by 3 -> The sum of its digits is a multiple of 3.
2. Divisible by 5 -> The last digit is 0 or 5.
If both rules are true, then the number is divisible by 15.
Steps to Check Divisibility by 15
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Check if the number is divisible by 3 (add up the digits and see if the sum is a multiple of 3).
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Check if the number is divisible by 5 (the last digit should be 0 or 5).
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If both conditions are true, then the number is divisible by 15.
Examples
Example 1: Is 345 divisible by 15?
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Check divisibility by 3: 3 + 4 + 5 = 12 (12 is a multiple of 3).
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Check divisibility by 5: 345 ends in 5 (It’s divisible by 5).
345 is divisible by 15.
Example 2: Is 780 divisible by 15?
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Check divisibility by 3: 7 + 8 + 0 = 15 (15 is a multiple of 3).
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Check divisibility by 5: 780 ends in 0 (It’s divisible by 5).
780 is divisible by 15.
Example 3: Is 276 divisible by 15?
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Check divisibility by 3: 2 + 7 + 6 = 15 (15 is a multiple of 3).
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Check divisibility by 5: 276 ends in 6 (It’s not divisible by 5).
276 is not divisible by 15.
Know the divisibilty rule of 16 here.
Try It Yourself:
Are they divisible by 15?
1. 1245
2. 3510
3. 4278
FAQs
1. What is the Divisibility Rule of 15?
A number is divisible by 15 if it is divisible by both 3 and 5.
Divisible by 3 → The Sum of the digits is divisible by 3
Divisible by 5 → Last digit is 0 or 5
Example:
45 → 4 + 5 = 9 (divisible by 3)
The last digit is 5
So, 45 is divisible by 15.
2. What Are the Numbers Divisible by 15?
Numbers divisible by 15 can be evenly divided by both 3 and 5.
They include multiples of 15: 15, 30, 45, 60, 75, etc.
Example:
75 ÷ 15 = 5
So, 75 is divisible by 15.
3. What Are the Divisibles of 15?
The divisors of 15 are the numbers that can divide 15 without leaving a remainder. These numbers are 1, 3, 5, and 15.
Example:
15 ÷ 1 = 15, 15 ÷ 3 = 5, 15 ÷ 5 = 3, and 15 ÷ 15 = 1.
So, the divisors of 15 are 1, 3, 5, and 15.