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The product of two consecutive positive odd numbers is 143. The numbers are
A7 and 9
B9 and 11
C13 and 15
D11 and 13
Answer & Solution
Correct answer: D. 11 and 13
1. Let the odd numbers be x and x + 2.
2. x(x + 2) = 143 gives x^2 + 2x - 143 = 0.
3. Factor: (x - 11)(x + 13) = 0, take positive root x = 11.
4. Numbers are 11 and 13.
_Source: Selina Concise Mathematics Class 10, Ch 5 Quadratic Equations (Mistral OCR'd PDF), section on word problems_
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