🥞 Ratio & scaling
The Recipe Scaler
Double the people at the table without wrecking the pancakes. There’s a trick, and it isn’t “a bit more of everything”.
Four at the table becomes eight.
So you reach for a bit more of everything.
That’s exactly how you wreck it.
The puzzle
A recipe is one idea wearing several numbers
Fluffy pancakes aren’t “300 g of flour”. They’re flour, milk and egg in a particular balance, and that balance is the recipe. The amounts you write down are that balance at one size.
Your turn. Drag the servings below and watch every ingredient grow together, while the shape underneath holds dead still.
Serves 4about 12 pancakes
The recipe’s shape. Slide all you like: this bar never moves. You multiply every ingredient by the same amount, so the balance between them can’t change. Size grows; shape holds.
The trap
More people, so… more of everything?
Saturday morning, and instead of four there are 8 of you. Here’s the shortcut nearly everyone reaches for: “four more people, so add four more to everything.” Four more grams, four more millilitres, four more eggs, four more spoons. Everyone got the same extra. Sounds fair. Answer before you look. Which batter do you eat?
The add-4 batter
flour 304 g (+4)
milk 504 ml (+4)
eggs 6 (+4)
sugar 6 tbsp (+4)
Rubbery. An omelette in a pancake costume.
The doubled batter
flour 600 g (×2)
milk 1000 ml (×2)
eggs 4 (×2)
sugar 4 tbsp (×2)
Same shape, twice the size. Proper pancakes.
Adding hands everyone the same amount.
Multiplying hands everyone the same treatment.
The why
Scaling changes the size. It never touches the shape.
Adding 4 hands every ingredient the same amount, but 4 ml is nothing to 500 ml of milk and everything to 2 eggs. Multiplying by 2 hands every ingredient the same treatment: each grows in proportion to what it already was. Don’t take the page’s word for it. Your turn: wreck the batter. Unlock the ratio, shove one ingredient around, and watch the mix object. Then lock it and try to break it.
Size: about 12 pancakes
Proper batter. The shape matches the recipe exactly.
Doing the sums
Find one serving first
Doubling is easy and halving is easy. The awkward ones are jumps like 6 servings down to 4: not double, not half, no obvious move. The move that always works: drop to ONE serving first, then multiply up. Divide, then times. Every awkward jump becomes two easy steps.
The recipe, as written: serves 6
450 g flour · 750 ml milk · 3 eggs
None of this is about pancakes.
The same locked shape is everywhere.
Screens, maps, music: one ratio, resized.
Same trick, hiding everywhere
Ratios don’t stay in the kitchen
Once you can spot a locked shape, you see it everywhere: something changes size while its ratio stays put. Tap one and see it.
Every one of these keeps a ratio locked while the size changes: exactly the batter, in disguise. Pick one and see how.
A recipe is one idea…
…wearing whatever size you need.
Change the size all you like. Never bend the shape. That’s the whole trick: in the kitchen, and everywhere it hides.
One more thing
So next time someone scales a recipe by adding (“two more people, chuck in a bit extra of everything”), ask them how many eggs that puts in, and watch them land on six for a four-egg job. Then show them the real move: drop to one serving, then times up. Divide, then multiply. Size grows, shape holds. This one’s yours now.