Skip to Content

Modular Arithmetic Using Modding First

Home | Abstract Algebra | Integers and Modular Arithmetic | Modular Arithmetic Using Modding First

Compute (45+38)mod7(45 + 38) \mod 7 by modding first.

Modular arithmetic often deals with finding the remainder when one number is divided by another. In this problem, we are working with the expression (45+38)mod7(45 + 38) \mod 7, which involves determining the remainder of a summed quantity modulo 7. A commonly used strategy here is to employ the technique of 'modding first'. This approach recommends performing the modulo operation on individual components before any other operations, like addition or multiplication. This technique helps to simplify calculations and reduce error margins, especially when handling larger numbers. Applying this method involves first performing the modulo operation separately on 45 and 38 before proceeding with their addition. It's typically more efficient and provides clearer intermediate results that can be easier to track and understand.

Conceptually, this problem is a demonstration of how modular arithmetic serves as a tool in different branches of mathematics and computer science, including cryptography and number theory. Understanding the properties of modular arithmetic can help in dealing with periodic functions and cyclic phenomena, since mod functions inherently produce cyclical results. As such, mastering this topic lays a foundation for more advanced mathematical simulations and problem-solving scenarios like those encountered in algorithms and complexity analysis.

Posted by Gregory 5 hours ago

Related Problems

Compute (45×38)mod7(45 \times 38) \mod 7 by modding first.

Prove that (ab)modn=(ab)modn(a \cdot b) \mod n = (a' \cdot b') \mod n when amodn=aa \mod n = a' and bmodn=bb \mod n = b'.