Subtopic: Mean, median, mode and standard deviation
Question Statement:
The mean and variance of a dataset are 16 and 25, respectively. The coefficient of variation of the dataset, in %, is __________. (Rounded off to 2 decimal places)
Official Answer Key:
31.20 to 31.30
Step-by-Step Solution & Explanation
Step 1 — standard deviation is the square root of the variance:
σ = √25 = 5
Step 2 — coefficient of variation:
CV = (σ/mean) × 100 = (5/16) × 100 = 31.25 %
Trap: using the variance directly (25/16 × 100 = 156.25%) — the CV is always defined on the standard deviation, so that the numerator and denominator carry the same units and the ratio is dimensionless.
Practice This in Real CBT Exam Interface
Test yourself with the official TCS-iON palette, virtual calculator, and immediate performance analytics.