The product of two consecutive positive odd integers is 143. What is the smaller of the two integers?
Answer and explanation
Correct answer: C. 11
- Step 1: Let integers be n and n + 2. Step 2. Set up equation: n(n + 2) = 143 => n² + 2n - 143 = 0. Step 3. Factor: (n + 13)(n - 11) = 0. Step 4. Since n > 0, n = 11. The two numbers are 11 and 13. Answer: 11. Why not the others: 9 gives 9 × 11 = 99; 13 is the larger integer; 15 gives 15 × 17 = 255.
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