Dividing by 5

Mental Math · Axiom Academy

LESSON Mental Math: Dividing by 5 Master the elegant trick of doubling and dividing by 10 to divide any number by 5 in seconds The trick is based on a simple algebraic fact. When we divide by 5, we can rewrite it as multiplying by 2 and dividing by 10. Let's see why these operations are equivalent. Here's the simple two-step process you'll use every time you need to divide by 5. With practice, you'll be able to do this in your head almost instantly. Let's work through the classic example step by step. Watch how we transform a division problem into simpler operations. Let's see how this trick works with different types of numbers - small, large, and even those that give decimal answers. Now it's your turn! Try these problems using the double-and-divide-by-10 method. Click "Show Answer" to check your work.

This is the written version of the interactive lesson above. See the full Mental Math course.