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Devon is 26 years older than his son Cooper. The sum of their ages is 50. Find their ages.
ADevon is 12 and Cooper is 38
BDevon is 36 and Cooper is 14
CDevon is 38 and Cooper is 12
DDevon is 40 and Cooper is 10
Answer & Solution
Correct answer: C. Devon is 38 and Cooper is 12
1. Let d be Devon's age and c be Cooper's age, giving the system d = c + 26 and c + d = 50.
2. Substitute c + 26 for d in the second equation: c plus (c plus 26) equals 50.
3. Simplify: 2c plus 26 equals 50, so 2c equals 24, giving c equals 12.
4. Substitute c = 12 into d = c + 26 to get d equals 38, and checking confirms 38 is 26 more than 12, and 38 plus 12 equals 50.
_Source: OpenStax Elementary Algebra (CC BY 4.0), Ch 5 "Systems of Linear Equations", section 5.4 Solve Applications with Systems of Equations_
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