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The random variable is normally distributed with mean, mu equals 60 kilobits for second, and standard deviation sigma equals 4 kilobits per second.
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Based on this information, we want to answer a through c below.
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This question is challenging understanding of how to work with normally distributed variables.
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To solve, we use the information given on the left and right here, and on the left we have information on how to map a z score onto probability for a standard normal distribution.
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Because our random variable x is not standard normal, it's just normal, we use the information on the right to convert all information in a through c to standard own form where z is x minus v over sigma.
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So with the information on the left and right, we should have all we need to solve.
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In a, we want to answer what is the probability that x is greater than 70? this is the same as asking what is the probability that z is greater than 70 minus me over sigma.
00:49
This is 2 .5, so we're looking for the probability z is greater than 2 .5...