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A recipe uses 1 cup mix, three quarters of a cup of milk and one egg for eight pancakes. How many eggs give 24 pancakes?
ATwo eggs are needed
BFour eggs are needed
CEight eggs are needed
DThree eggs are needed
Answer & Solution
Correct answer: D. Three eggs are needed
1. The recipe fixes a ratio of 1 egg per 8 pancakes.
2. Multiply the target amount by that ratio: 24 pancakes times 1 egg per 8 pancakes.
3. The pancake units cancel, leaving 24 divided by 8, which is 3 eggs.
4. Balanced equations are used in exactly this way, with coefficients in place of recipe amounts.
_Source: OpenStax Chemistry (CC BY 4.0), Ch 4 "Stoichiometry of Chemical Reactions", section 4.3 Reaction Stoichiometry_
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