NumericalModerate2 marks
6(c)
If (7m + 2n) / (7m - 2n) = 5 / 3, use properties of proportion to find
(m² + n²) / (m² - n²)
Topic: Shares, dividend and return
Previous-year question practice database
Answer
Exam answer
From part (i): m:n = 8:7.
Let m=8k, n=7k.
(m²+n²)/(m²−n²) = (64k²+49k²)/(64k²−49k²) = 113/15.
Answer: 113/15.
Explanation
Use the ratio m:n=8:7 obtained in part (i).
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