Ratio Rescue Scaling Worksheet
Ratio Rescue
Culinary Lab: The Scaling Up Correction Sheet
NAME:
DATE:
The Recipe Problem
"A recipe requires \( \frac{1}{3} \) cup of milk for each \( \frac{1}{4} \) cup of water. How many cups of water are needed for each cup of milk?"
Goal: Unit Rate
A unit rate is a comparison where the second quantity is exactly 1. We need the amount of water "per 1 cup" of milk.
Target: 1 Cup of Milk
Scaling Up Method
We use a ratio table and multiply both parts of the ratio by the same number to reach our target unit of 1.
Scale Factor: × 3
The Scaling Path: Finding Choice B
Milk (Cups)
Water (Cups)
\( \frac{1}{3} \)
× 3
\( \frac{1}{4} \)
× 3
1
\( \frac{3}{4} \)
Why scale by 3? Because \( \frac{1}{3} \times 3 = 1 \). This gets us to our target of "per cup of milk." To keep the ratio proportional, we must also scale the water by 3.
Mistake Analysis
Why were these traps so tempting?
Wrong Operation A 1/12
The "No-Scaling" Trap
Students reached this by multiplying the two numbers together: \( \frac{1}{3} \times \frac{1}{4} = \frac{1}{12} \).
The Fix: In the scaling method, we aren't just looking for any product. We are choosing a specific factor that changes our target quantity to 1.
Wrong Target D 1 1/3
The "Flipped Table" Trap
Students scaled the Water side to 1 (multiplying by 4). This finds "cups of milk per cup of water."
The Fix: Always circle the word after "per" or "each." That is your target unit that must become 1 in your table.
My Scaling Check
Look at the scaling table on the previous page. Why is it important to multiply both sides of the table by the same number?
Ratio Rescue • Scaling Up Method Mastery • Culinary Math Lab
