Modular arithmetic is based on the remainder after division. To solve each problem, first add or multiply the numbers, then divide by the modulus and find the remainder.[br][br]For example: 17 (mod 5) =2 [br]it is because when we do 17/5 it leaves a remainder of 2. [br][br][br]

This applet helps students practice modular addition and multiplication using a picture and interactive questions. It shows how to find the remainder and understand modular arithmetic.[br][br]Classroom use:[br][br]This activity can be used in class to introduce or review modular arithmetic. Students can use the picture to understand the concept and answer the questions to check their understanding.[br]