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Questions › JNU › JNU SIS 2012 › Q18
4 marks, −1Statistics › Random variables and standard distributions › The normal distributionEasyabout 1 min

JNU SIS 2012 Question 18: Random variables and standard distributions

The score of students in a certain examination is normally distributed with mean 46 and variance 400. Given Φ(⋅8)=0⋅788\Phi(\cdot 8) = 0\cdot 788Φ(⋅8)=0⋅788, where Φ\PhiΦ denotes the standard normal cumulative distribution function, the probability of a student scoring less than 30 is

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The score of students in a certain examination is normally distributed with mean 46 and variance 400. Given Φ(· 8) = 0· 788, where Φ denotes the standard normal cumulative distribution function, the probability of a student scoring less than 30 is (A) 0· 212 (B) 0· 112 (C) 0· 222 (D) 0· 111

Also written as: The score of students in a certain examination is normally distributed with mean 46 and variance 400. Given Phi(* 8) = 0* 788, where Phi denotes the standard normal cumulative distribution function, the probability of a student scoring less than 30 is

Random variables and standard distributions has come up 173 times in 7 exams since 2005.

What this question tests

This question is on The normal distribution, part of Random variables and standard distributions in Statistics.

The bell curve: standardising, tail probabilities and approximations.

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Question from the JNU SIS 2012 paper. Solutions are TestStop's own. Not affiliated with or endorsed by any examination authority.