Because recipes are lying liars sometimes. They’ll call for “1 cup minus 1/8 cup” just to test your patience. But knowing that 1/2 + 1/3 = 5/6 unlocks a secret: you can double and half recipes with confidence.
For example, if you need to double a recipe that asks for 1/2 cup plus 1/3 cup, you’d need 1 and 2/3 cups. (That’s 10/6, which simplifies to 5/3. Just trust me.) But we don’t need to go there today. Today, we just need to get dinner on the table.
And next time someone asks you what’s half of 3/4 cup, you can smirk and say, “That’s 3/8 cup, of course.” They’ll think you’re a wizard. Let them.
How accurate are your measuring cups? | King Arthur Baking