At a mean of 95 pounds per passenger and standard deviation of 35 pounds, multiplying this with the total number of passengers = 200, results in:
absolute mean = 95 * 200 = 19,000
absolute std dev = 35 * 200 = 7,000
Calculating for the z score:
z = (x – u) / s
where x is sample value = more than 20,000; u is the sample mean = 19,000; s is std dev = 7,000
z = (20,000 – 19,000) / 7,000
z = 0.143
From the distribution tables,
P (z = 0.14) = 0.5557
Therefore a 55.57% chance that it will be more than 20,000 pound limit