The length of a social media interaction is normally distributed with a mean of 3 minutes and a standard deviation of 0.4 minutes. what is the probability that an interaction lasts longer than 4 minutes? 0.0045254 0.043351 0.0095254 0.006209

For a normally distributed data, with mean, μ, and standard deviation, σ, the probability that a randomly selected data, X, is less than a given value, x, is given by

and the probability that a randomly selected data, X, is greater than a given value, x, is given by


Given that the length of a social media interaction is normally distributed with a mean of 3 minutes and a standard deviation of 0.4 minutes, the probability that an interaction lasts longer than 4 minutes is given by


We use the normal distribution table or calculator to evalute that P(X < 2.5) = 0.99379

Therefore, the probability that an interaction lasts longer than 4 minutes = 1 - 0.99379 = 0.00621
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