AlgebraMediumChoosing the system for a word problem
Algebra practice question
A stall sold large and small candles. Two large and three small candles cost $16, and a large candle costs $3 more than a small one. If L and S are the prices of a large and a small candle, which system represents this?
- A. 2L + 3S = 16 and L − S = 3Correct
- B. 2L + 3S = 16 and S − L = 3
- C. 3L + 2S = 16 and L − S = 3
- D. 2L + 3S = 16 and L + S = 3
Answer: A. 2L + 3S = 16 and L − S = 3
Two large plus three small is 16; large minus small is 3. (Solution: L = 5, S = 2.)
Why the other answers are wrong
- B. 2L + 3S = 16 and S − L = 3
- S − L = 3 makes the small candle dearer.
- C. 3L + 2S = 16 and L − S = 3
- 3L + 2S swaps the counts.
- D. 2L + 3S = 16 and L + S = 3
- L + S = 3 misreads the difference as a sum.
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