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A sandwich needs 2 slices of bread and 1 slice of cheese. With 28 slices of bread and 11 of cheese, what results?
A14 sandwiches, with 3 cheese slices left
B11 sandwiches, with 6 bread slices left
C22 sandwiches, with 5 bread slices left
D11 sandwiches, with 3 cheese slices left
Answer & Solution
Correct answer: B. 11 sandwiches, with 6 bread slices left
1. Bread alone would allow 28 divided by 2, which is 14 sandwiches.
2. Cheese alone would allow 11 divided by 1, which is 11 sandwiches.
3. The smaller figure wins, so 11 sandwiches are made and cheese is the limiting ingredient.
4. Those 11 sandwiches use 22 slices of bread, leaving 28 minus 22, which is 6 slices.
5. Bread is therefore present in excess.
_Source: OpenStax Chemistry (CC BY 4.0), Ch 4 "Stoichiometry of Chemical Reactions", section 4.4 Reaction Yields_
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