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 42.
The divisibility rule for 42 is a method by which we can find out if a number is divisible by 42 or not without using the division method. Check whether 252 is divisible by 42 with the divisibility rule.
Step 1: Check if the number is divisible by both 6 and 7.
For divisibility by 6, the last digit must be even, and the sum of the digits must be divisible by 3. For 252, the last digit is 2 (even), and the sum of the digits is 2 + 5 + 2 = 9, which is divisible by 3.
For divisibility by 7, double the last digit and subtract it from the rest of the number. For example, 2 × 2 = 4, and 25 - 4 = 21. Since 21 is divisible by 7, the rule holds.
Step 2: Since 252 meets both criteria, it is divisible by 42.
Learning the divisibility rule will help kids master division. Let’s learn a few tips and tricks for the divisibility rule of 42.
The divisibility rule of 42 helps us to quickly check if the given number is divisible by 42, but common mistakes like calculation errors lead to incorrect results. Here we will understand some common mistakes that will help you avoid them.
Is the number of pages in a book, 420, divisible by 42?
Yes, 420 is divisible by 42.
To determine if 420 is divisible by 42, we need to check divisibility by both 6 and 7 (since 42 = 6 x 7).
1) Check divisibility by 6: 420 is even, and the sum of its digits (4 + 2 + 0 = 6) is divisible by 3, so 420 is divisible by 6.
2) Check divisibility by 7:
Multiply the last digit by 2: 0 × 2 = 0.
Subtract from the rest: 42 - 0 = 42.
42 is divisible by 7.
Since 420 is divisible by both 6 and 7, it is divisible by 42.
A club has 294 members. Can they be evenly divided into groups of 42?
Yes, 294 can be evenly divided by 42.
To check if 294 is divisible by 42, we need to check divisibility by both 6 and 7.
1) Check divisibility by 6: 294 is even, and the sum of its digits (2 + 9 + 4 = 15) is divisible by 3, so 294 is divisible by 6.
2) Check divisibility by 7:
Multiply the last digit by 2: 4 × 2 = 8.
Subtract from the rest: 29 - 8 = 21.
21 is divisible by 7.
Since 294 is divisible by both 6 and 7, it is divisible by 42.
Is the total number of seats in a theater, 336, divisible by 42?
Yes, 336 is divisible by 42.
To determine if 336 is divisible by 42, check for divisibility by both 6 and 7.
1) Check divisibility by 6: 336 is even, and the sum of its digits (3 + 3 + 6 = 12) is divisible by 3, so 336 is divisible by 6.
2) Check divisibility by 7:
Multiply the last digit by 2: 6 × 2 = 12.
Subtract from the rest: 33 - 12 = 21.
21 is divisible by 7.
Since 336 is divisible by both 6 and 7, it is divisible by 42.
A concert venue has 200 seats and wants to arrange them in sections of 42. Is this possible?
No, 200 is not divisible by 42.
To check if 200 is divisible by 42, check for divisibility by both 6 and 7.
1) Check divisibility by 6: 200 is even, but the sum of its digits (2 + 0 + 0 = 2) is not divisible by 3, so 200 is not divisible by 6.
Since 200 is not divisible by 6, it cannot be divisible by 42.
A puzzle has 504 pieces. Can these pieces be arranged into sets of 42?
Yes, 504 can be arranged into sets of 42.
To determine if 504 is divisible by 42, check for divisibility by both 6 and 7.
1) Check divisibility by 6: 504 is even, and the sum of its digits (5 + 0 + 4 = 9) is divisible by 3, so 504 is divisible by 6.
2) Check divisibility by 7:
Multiply the last digit by 2: 4 × 2 = 8.
Subtract from the rest: 50 - 8 = 42.
42 is divisible by 7.
Since 504 is divisible by both 6 and 7, it is divisible by 42.
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.