If a/b = 4/5 and b/c = 15/16, find the value of (c^2 - ... – Arithmetic

Arithmetichard · Past Paper

If a/b = 4/5 and b/c = 15/16, find the value of (c^2 - a^2) / (c^2 + a^2).

A1/7

B7/25

C3/4

DNone

✓ Correct Answer: B — 7/25

a/c = (a/b)*(b/c) = (4/5)*(15/16) = 3/4. Let a=3k, c=4k. Expression = (16k^2 - 9k^2)/(16k^2 + 9k^2) = 7/25.

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