NIMCET 2020 — Reasoning PYQ

Step 1: Decode the given expression

The problem gives us the mathematical expression:

$$X+Y+Z$$

Let's break this down into separate parts based on rule iii (A + B \implies A < B):

• X + Y \implies X < Y ($X$ is younger than $Y$)

• Y + Z \implies Y < Z ($Y$ is younger than $Z$)

Combining these two inequalities, we get the complete age hierarchy:

X < Y < Z

This means $Z$ is the oldest, followed by $Y$, and $X$ is the youngest.

Step 2: Decode the given options to find a match

Now, let us convert the mathematical relations of the options back using rule ii (A - B \implies B < A, meaning $B$ is younger than $A$):

• Option A: $Y-X-Z$

  • Y - X \implies X < Y

  • X - Z \implies Z < X

  • Combined: Z < X < Y (Incorrect)

• Option B: $Z-Y-X$

  • Z - Y \implies Y < Z ($Y$ is younger than $Z$)

  • Y - X \implies X < Y ($X$ is younger than $Y$)

  • Combined: X < Y < Z (Matches perfectly!)

• Option C: $Z-X-Y$

  • Z - X \implies X < Z

  • X - Y \implies Y < X

  • Combined: Y < X < Z (Incorrect)

• Option D: $X-Y-Z$

  • X - Y \implies Y < X

  • Y - Z \implies Z < Y

  • Combined: Z < Y < X (Incorrect)

Therefore, the expression $Z-Y-X$ represents the exact same logical arrangement as $X+Y+Z$.