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In: Statistics and Probability

Q1) In a test, the time taken to solve the questions is normally distributed with mean...

Q1) In a test, the time taken to solve the questions is normally distributed with mean μ and standard deviation σ. It is found that 4% of the population take less than 5 minutes to get to solve questions, and 70% take less than 25 minutes.

i. Find the values of mean and variance of time distribution.

ii. Find the Interquartile range of time

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