Question

The amount of time you need to complete a mathematics placement test is approximately normal distribution with a mean 45 minutes wiith a standard deviation six minutes. Find the probability of students will complete the test within 45 minutes

it takes from me approximately normally distributed with a mean of 30 minutes to get to work and a standard division of 4 minutes what time should I leave home to make sure that I have a 95% chance of being work by 7:30

Answer 1

Hello

Q - 1 -

Given that, in the normal distribution,

Mean =	45.000
Standard Deviation =	6.000

Q - 2 -

Given that:

Mean =	30.000
Standard Deviation =	4.000

95% chance means p value of 0.95 and z-score of 1.64

Hence, required X = (1.64*4)+ 30 = 36.5794 min

Hence, you should leave latest by 7:30 - 36.58 min = 06:53 (Or to be precise 06:53:25)

Thanks!

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