← Why the Formula Works · Lesson 2 of 4
Dividing by a fraction
"Turn it upside down and multiply" is a rule without a reason. The reason is a question: how many of these fit into that?
3 ÷ ½ asks how many halves fit into 3. Each whole holds two halves, so three wholes hold six. Dividing by a half is the same as multiplying by two.
The same picture works for any fraction. 2 ÷ ¼ asks how many quarters fit into 2: four in each whole, so eight.
Using "how many fit?", what is 2 ÷ ¼?
A lesson is kept once you've answered the question and written at least 8 words. Nobody grades it; it stays on this device.