The arc length of the curve is
which has a value of about 5.99086.
Let . Split up the interval of integration into 10 subintervals,
[0, 1/2], [1/2, 1], [1, 3/2], ..., [9/2, 5]
The left and right endpoints are given respectively by the sequences,
with .
These subintervals have midpoints given by
Over each subinterval, we approximate with the quadratic polynomial
so that the integral we want to find can be estimated as
It turns out that
so that the arc length is approximately
Answer:
This value means that his shoe size is 2.9 deviations above the population mean.
And we can find the approximate percentile for his measure like this:
This correspond to the 99.8 percentile, so then his shoe size is 99.8% above all the shoe sizes.
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the shoe size of a population, and for this case we know the distribution for X is given by:
Where represent the mean and
the population standard deviation.
For this case we know that a man obtain a z score of z=2.9
This value means that his shoe size is 2.9 deviations above the population mean.
And we can find the approximate percentile for his measure like this:
This correspond to the 99.8 percentile, so then his shoe size is 99.8% above all the shoe sizes.