Question

It has been determined that the mean amount of time that computer science majors spend on homework each week is approximately normally distributed with a mean of 15.2 hours and standard deviation 3.1 hours. What is the probability that a randomly selected computer science major will spend more than 14.5 hours on homework in a given week?

Answer #1

Solution:

Given that,

mean = = 15.2 hours

standard deviation = = 3.1 hours

p ( x > 14.5 )

= 1 - p (x < 14.5)

= 1 - p ( x - / ) < ( 14.5 - 15.2/ 3.1 )

= 1 - p ( z < - 0.7 / 3.1 )

= 1 - p ( z < - 0.23 )

Using z table

= 1 - 0.4090

= 0.5910

Probability = 0.5910

Suppose that the amount of time INTI International University
students spend in the library
per week is normally distributed. A sample of 6 students is
selected at random, and the
sample mean computed as 13.83 hours with the standard deviation of
2.86 hour. Test at 1%
significance level whether the mean number of hours spend in the
library per week is less
than 15 hours.

the amount of money that students spend on their cell phones per
week in normally distributed with a mean of 52.00 and standard
deviation of 6.00. 1.2.1 What is the probability that a student
studies for more that 60.00 per week? 1.2.2 find the probability
that the mean amount of money on cell phones for three randomly
selected students is less than 60.66 per week.

A survey of 20 randomly selected adult men showed that the mean
time they spend per week watching sports on television is 9.34
hours with a standard deviation of 1.34 hours.
Assuming that the time spent per week watching sports on
television by all adult men is (approximately) normally
distributed, construct a 90 % confidence interval for the
population mean, μ .
Round your answers to two decimal places.
Lower bound: Enter your answer; confidence interval, lower
bound
Upper bound:...

The times per week a student uses a lab computer are normally
distributed, with a mean of 6.3 hours and a standard deviation of
1.2 hours. A student is randomly selected. Find the following
probabilities.
(a) Find the probability that the student uses a lab computer
less than 5 hours per week.
(b) Find the probability that the student uses a lab computer
between 6 and 8 hours per week.
(c) Find the probability that the student uses a lab...

The times per week a student uses a lab computer are normally
distributed, with a mean of 6.1 hours and a standard deviation of
1.3 hours. A student is randomly selected. Find the following
probabilities.
(a) Find the probability that the student uses a lab computer
less than 4 hours per week.
(b) Find the probability that the student uses a lab computer
between 7 and 8 hours per week.
(c) Find the probability that the student uses a lab...

The times per week a student uses a lab computer are normally
distributed, with a mean of 6.2 hours and a standard deviation of
1.3 hours. A student is randomly selected. Find the following
probabilities.
(a) Find the probability that the student uses a lab computer
less than 4 hours per week.
(b) Find the probability that the student uses a lab computer
between 6 and 8 hours per week.
(c) Find the probability that the student uses a lab...

The time a student spends learning a computer software package
is normally distributed with a mean of 8 hours and a standard
deviation of 1.5 hours. A student is selected at random.
a)What is the probability that the student spends at least 6
hours learning the software package?
b) What is the probability that the student spends between 6.5
and 8.5 hours learning the software package?
c) If only 7% of the students spend more than k hours learning
the...

The amount of time required to assemble a component on a factory
assembly line is normally distributed with a mean of 3.1 minutes
and a standard deviation of 0.6 minute. Find the probability that a
randomly selected employee will take the given amount of time to
assemble the component. (Round your answers to four decimal
places.)
(a) more than 3.8 minutes
(b) between 1.8 and 2.5 minutes

The amount of time required to assemble a component on a factory
assembly line is normally distributed with a mean of 3.1 minutes
and a standard deviation of 0.7 minute. Find the probability that a
randomly selected employee will take the given amount of time to
assemble the component. (Round your answers to four decimal
places.)
(a) more than 3.7 minutes
(b) between 1.8 and 2.6 minutes

The owner of a computer repair shop has determined that their
daily revenue has mean $7200 and standard deviation $1200. The
daily revenue is normally distributed. a) What is the probability
that a randomly selected day will have a revenue of at most $7000?
b) The daily revenue for the next 30 days will be monitored. What
is the probability that the mean daily revenue for the next 30 days
will exceed $7500?

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 6 minutes ago

asked 14 minutes ago

asked 22 minutes ago

asked 24 minutes ago

asked 39 minutes ago

asked 44 minutes ago

asked 47 minutes ago

asked 48 minutes ago

asked 57 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago