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When Mason commutes to work, the amount of time it takes him to arrive is normally distributed with a mean of 38 minutes and a standard deviation of 3 minutes. Out of the 283 days that Mason commutes to work per year, how many times would his commute be longer than 41 minutes, to the nearest whole number?

When Mason commutes to work, the amount of time it takes him to arrive is normally distributed with a mean of 3838 minutes and a standard deviation of 33 minutes. Out of the 283283 days that Mason commutes to work per year, how many times would his commute be longer than 4141 minutes, to the nearest whole number?

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Q. When Mason commutes to work, the amount of time it takes him to arrive is normally distributed with a mean of 3838 minutes and a standard deviation of 33 minutes. Out of the 283283 days that Mason commutes to work per year, how many times would his commute be longer than 4141 minutes, to the nearest whole number?
  1. Identify Information: Identify the given information and what we need to find.\newlineMason's commute time is normally distributed with a mean μ\mu of 3838 minutes and a standard deviation σ\sigma of 33 minutes. We need to find out how many days out of 283283 his commute time will be longer than 4141 minutes.
  2. Calculate z-score: Calculate the z-score for the commute time of 4141 minutes.\newlineThe z-score formula is: z=(Xμ)/σz = (X - \mu) / \sigma, where XX is the value we are comparing to the mean.\newlineFor Mason's commute time, z=(4138)/3=3/3=1z = (41 - 38) / 3 = 3 / 3 = 1.
  3. Find Probability: Use the z-score to find the probability that Mason's commute time is longer than 4141 minutes.\newlineWe look up the z-score of 11 in the standard normal distribution table or use a calculator to find the area to the right of z=1z = 1. This area represents the probability that a given day's commute time will exceed 4141 minutes.\newlineThe area to the left of z=1z = 1 is approximately 0.84130.8413, so the area to the right (which is what we want) is 10.8413=0.15871 - 0.8413 = 0.1587.
  4. Calculate Number of Days: Calculate the number of days Mason's commute will be longer than 4141 minutes.\newlineWe multiply the probability by the total number of commuting days.\newlineNumber of days = 0.1587×28344.91210.1587 \times 283 \approx 44.9121.
  5. Round Result: Round the result to the nearest whole number, as we cannot have a fraction of a day.\newlineMason's commute will be longer than 4141 minutes on approximately 4545 days out of 283283.

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