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GATE 2020 ME (ME2) – Question 9

General Aptitude · Quantitative Aptitude: Algebra, Geometry and Mensuration · 2 marks · Multiple choice

An engineer measures X, Y and Z. Their product XY varies linearly with Z as shown. Which statement is FALSE?

Diagram for GATE 2020 ME (ME2) question 9
  1. For fixed Z, X is proportional to Y.
  2. For fixed Y, X is proportional to Z.
  3. For fixed X, Z is proportional to Y.
  4. XY/Z is constant.

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Show answer and explanation

Correct answer: (A) For fixed Z, X is proportional to Y.

Explanation

The straight line through the origin means XY=kZ. With fixed Z, X=kZ/Y, so X is inversely proportional to Y. Thus **A is false**. Holding either X or Y fixed gives the other proportionalities; XY/Z=k is constant.