Still, waiting for the server? How does your web browser get a file from the Internet? Your computer sends a request for the file to a web server, and the webserver sends back

a response. For one particular web server, the time (in seconds) after the start of an hour at which a request is received can be modeled by a uniform distribution on the interval from 0 to 3600 seconds.

a. Draw a density curve to model the amount of time after an hour at which a request is received by the webserver. Be sure to include scales on both axes.

b. About what proportion of requests are received within the first 5 minutes (300 seconds) after the hour?

c. Find the interquartile range of this distribution.

Short Answer

Expert verified

Part (a) f(x)0.00027778whenf(x)0.00027778

Part (b) About 0.0833 of the requests are received within the first 300 seconds after the hour.

Part (c) Interquartile range of the distribution is 1800 seconds.

Step by step solution

01

Part (a) Step 1: Given information

On interval 0x3600, the distribution was modeled using a uniform distribution.

Such that

a=0

And

b=3600

Time for receiving requests,

0x300s

02

Part (a) Step 2: Concept

A density curve is always on or above the horizontal axis.

03

Part (a) Step 3: Calculation

The density curve for a uniform distribution is proportional to the difference between the boundaries.

In the space between the two limits,

f(x)=1b-a=13600-0=136000.00027778

With

0x3600

04

Part (b) Step 1: Calculation

The likelihood that the time it takes to receive requests is less than 300 seconds will be represented by the area beneath the density curve for all values before 300

Note that

The rectangle will be the area beneath the density curve.

With

Width,W=300-0=300

And

Height, H=f(x)=0.00027778

Then

P(0<x<300)=Areaofrectangle=W×H=300×0.000277780.0833

Therefore,

About 0.0833of the requests are received within the first 300seconds (5minutes) after the hour.

05

Part (c) Step 1: Calculation

The difference between the first and third quartiles is the interquartile range.

The 1st quartile's characteristic demonstrates that 25% of the data values are below it.

The 3rd quartile's characteristic demonstrates that 75% of the data values are below it.

Despite the fact that the distribution is uniform between 0 and 3600, the 1st quartile contains 25% of the data values below it, implying that 25% of the distribution will be one-fourth of the interval.

Then

Q3=3600×34=2700

The interquartile range is the difference between the first and third quartiles.

Thus,

IQR=Q3Q1=1800

Both the interquartile range and the data values will be expressed in the same units.

Therefore,

The interquartile range is 1800seconds.

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