GATE 2016 ME (ME3) – Question 14
The area (in percentage) under standard normal distribution curve of random variable Z within limits from −3 to +3 is __________
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Correct answer: 99.6 to 99.8
Explanation
Standardise with Z=(X−μ)/σ. The required probability is P(−3≤Z≤3)=Φ(3)−Φ(−3)=0.9973002. Multiplying by100 gives **99.7300%**, inside the official99.6–99.8 interval. The percentage, rather than the fraction, is requested.