The third proportional to the numbers a and b is ab, which of the following statements is true?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. a2 = b
Third proportional c to a and b satisfies:
a : b = b : c → c = b2 / a
Given c = ab
So, ab = b2 / a
Multiply both sides by a → a2b = b2
Divide both sides by b (b ≠ 0) → a2 = b