Final answer:
Annie worked for 5 hours to prepare 30 kilograms of dough.
Step-by-step explanation:
Let's use a proportion to solve this problem. We can set up the equation:
2 hours / 12 kilograms = x hours / 30 kilograms
Cross multiplying, we get:
2 * 30 = 12 * x
Simplifying, we find that x = 5. So, Annie worked for 5 hours to prepare 30 kilograms of dough.
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