Division of fractions is the main theme in sixth grade. Old textbooks just stated the formula for doing the operation. But the new textbooks use a graph, or go back to visualizing the original problem to explain the relationship between fractions, and from this deduce the principle of multiplying by the reciprocal.
分數相除是六年級數學的重頭戲，舊課本直接說明運算方式，新教材則採取線段圖示法、或回歸題目情境說明分數之間的關係，從中推論顛倒相除的原理。