Definitions from a mathematical mouse
addition: the process of putting together one number/amount with at least one other number/amount, which finds the total or sum of them.
My Youtube videos below demonstrate how to understand formal methods for addition. The great thing is you can watch them as many times as you need and if you ever forget part of the method, you can simply watch it again anytime you want...but not when you're supposed to be sleeping in bed!
Of course, all great mousematicians know that sometimes using mental methods can be the best strategy and sometimes using formal methods is the best method. Don't always use the same approach - use the best approach!
TdM Brie-Anna de Mouse, creator and star of Maths with a Mouse
Before we get started with formal methods, perhaps you need to brush up on your mental addition and subtraction skills or simply want to play some great addition and subtraction games. If you do, push the big yellow button now!
Addition without carrying
Addition with carrying
Ready to use what you have learned? Have a go at these great Brain Workouts from mathplayground.com. Try to use your understanding of formal addition to help find solutions.
Warning: it might not be that easy!
Addition with decimals