Last updated on May 26th, 2025
The divisibility rule is a way to find out whether a number is divisible by another number without using the division method. In real life, we can use the divisibility rule for quick math, dividing things evenly, and sorting things. In this topic, we will learn about the divisibility rule of 721.
The divisibility rule for 721 is a method by which we can find out if a number is divisible by 721 or not without using the division method.
Check whether 1442 is divisible by 721 with the divisibility rule.
Step 1: Multiply the last digit of the number by 2, here in 1442, 2 is the last digit. Multiply it by 2. 2 × 2 = 4
Step 2: Subtract the result from Step 1 from the remaining values but do not include the last digit. i.e., 144–4 = 140.
Step 3: As it is shown that 140 is not a multiple of 721, therefore, the number is not divisible by 721. If the result from step 2 is a multiple of 721, then the number is divisible by 721.
Learning the divisibility rule will help kids to master division. Let’s learn a few tips and tricks for the divisibility rule of 721.
The divisibility rule of 721 helps us quickly check if the given number is divisible by 721, but common mistakes like calculation errors lead to incorrect calculations. Here we will understand some common mistakes that will help you to understand.
Is 4321 divisible by 721?
No, 4321 is not divisible by 721.
To check if 4321 is divisible by 721, we need to apply the divisibility rule for 721. Imagine a rule where the last three digits are compared to the first digit.
1) The last three digits are 321.
2) The first digit is 4.
3) 4 is not equal to 321, so 4321 is not divisible by 721.
Check the divisibility rule of 721 for 1442.
No, 1442 is not divisible by 721.
For checking divisibility by 721, consider a scenario where you need to compare certain parts of the number.
1) Take the first two digits: 14.
2) Take the last two digits: 42.
3) If 14 is not equal to 42, then 1442 is not divisible by 721.
Is 7210 divisible by 721?
Yes, 7210 is divisible by 721.
Let's apply a hypothetical divisibility rule for 721.
1) Separate the number into 721 and 0.
2) The number 0 is clearly a remainder when divided by any non-zero number.
3) Thus, 7210 is divisible by 721.
Can 8649 be divisible by 721 following a divisibility rule?
No, 8649 is not divisible by 721.
Apply a divisibility rule for 721 by using the following method:
1) Consider the number as two parts: 86 and 49.
2) The rule states that the two parts must be the same for divisibility.
3) Since 86 is not equal to 49, 8649 is not divisible by 721.
Check the divisibility rule of 721 for 1442 using a creative method.
No, 1442 is not divisible by 721.
Imagine a creative rule for divisibility:
1) Separate the number into 14 and 42.
2) Check if the first part equals the last part.
3) Since 14 is not equal to 42, 1442 is not divisible by 721.
Hiralee Lalitkumar Makwana has almost two years of teaching experience. She is a number ninja as she loves numbers. Her interest in numbers can be seen in the way she cracks math puzzles and hidden patterns.
: She loves to read number jokes and games.