Discovering New Formulas for Divisibility by 7 in Mathematics
The world of mathematics often surprises us with new discoveries, especially when it comes to divisibility rules. Historically, mathematicians have developed various rules to check divisibility quickly, but the specific formula for divisibility by 7 remains less known. This article delves into the development of a new formula for divisibility by 7, how it works, and its significance.
Traditional Divisibility Rule for 7
Traditionally, checking whether a number is divisible by 7 involves a simple technique. You take the last digit of the number, double it, and subtract it from the rest of the number. If the result is 0 or divisible by 7, then the original number is divisible by 7. For example, to check if 1603 is divisible by 7:
Double the last digit: 3 x 2 6 Subtract from the rest of the number: 160 - 6 154 Repeat the process: 15 - (4 x 2) 15 - 8 7 Since 7 is divisible by 7, 1603 is also divisible by 7.Chika Ofili and the New Formula
A significant development in this area came in 2017 when Chika Ofili, a young student at Westminster Under School, discovered a new rule for divisibility by 7. In an interview, Solomon, a mathematician, mentioned hearing about Chika Ofili and the test for divisibility by 7. Chika's formula simplifies the process and provides a more straightforward way to check for divisibility.
According to Chika Ofili, the new rule is as follows: multiply the last digit of a number by 5 and then add it to the remaining part of the number. This sum should be divisible by 7 for the original number to be divisible by 7. For example, to check if 1603 is divisible by 7 using Chika's formula:
Multiply the last digit by 5: 3 x 5 15 Add it to the remaining part: 160 15 175 Since 175 is divisible by 7 (175 รท 7 25), 1603 is also divisible by 7.Mathematical Significance and Practical Applications
The new formula by Chika Ofili is not only an interesting mathematical discovery but also has practical implications. It simplifies the process of checking divisibility by 7, making it faster and easier for students and professionals alike. This rule is particularly useful in number theory and can be employed in various mathematical problems, such as simplifying fractions or solving equations.
Conclusion
The discovery by Chika Ofili of a new formula for divisibility by 7 marks an important contribution to the field of mathematics. It simplifies an existing rule and provides a more straightforward method for checking divisibility, enhancing the understanding and application of mathematical principles.
For more information on mathematical discoveries and rules, stay tuned as new findings continue to emerge, enriching our knowledge of this fascinating subject.