Question

A survey of high school students revealed that the number of soft drinks consumed per month...

A survey of high school students revealed that the number of soft drinks consumed per month was normally distributed with a mean of 25 and standard deviation 15. A sample of 36 students was selected. What is the probability that the average number of soft drinks consumed per month for the sample was between 28.7 and 30 soft drinks

Homework Answers

Answer #1

Given

= 25 , = 15

Using central limit theorem,

P( < x) = P(Z < ( x - ) / ( / sqrt(n) ) )

So,

P(28.7 < < 30) = P( < 30) - P( < 28.7)

= P(Z < ( 30 - 25) / ( 15 / sqrt(36)) ) - P(Z < ( 28.7 - 25) / ( 15 / sqrt(36)) )

= P(Z < 2) - P(Z < 1.48)

= 0.9772 - 0.9306 ( from Z table)

= 0.0466

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
a survey among freshmen at a certain university revealed that the number of hours spent studying...
a survey among freshmen at a certain university revealed that the number of hours spent studying the week before finals exams was normally distributed with mean 25 and standard deviation 15. a sample of 36 students was selected. what is the probability that the average time spent studying for the sample was between 28.0 and 30 hours studying? round to four decimal places.
A survey among freshmen at a certain university revealed that the number of hours spent studying...
A survey among freshmen at a certain university revealed that the number of hours spent studying the week before final exams was normally distributed with mean 25 and standard deviation 15. A sample of 36 students was selected. What is the probability that the average time spent studying for the sample was between 29.0 and 30 hours studying? Round to 4 decimal places.
A survey among freshmen at a certain university revealed that the number of hours spent studying...
A survey among freshmen at a certain university revealed that the number of hours spent studying the week before final exams was normally distributed with mean 25 and standard deviation 15. A sample of 36 students was selected. What is the probability that the average time spent studying for the sample was between 29.2 and 30 hours studying? Write only a number as your answerRound to 4 decimal places (for example 0.0048 ). Do not write as a percentage .
The number of pizzas consumed per month by university students is normally distributed with a mean...
The number of pizzas consumed per month by university students is normally distributed with a mean of 9 and a standard deviation of 5. A. What proportion of students consume more than 12 pizzas per month? Probability = B. What is the probability that in a random sample of size 10, a total of more than 110 pizzas are consumed? (Hint: What is the mean number of pizzas consumed by the sample of 10 students?) Probability =
The number of pizzas consumed per month by university students is normally distributed with a mean...
The number of pizzas consumed per month by university students is normally distributed with a mean of 7 and a standard deviation of 4. A. What proportion of students consume more than 9 pizzas per month? Probability = B. What is the probability that in a random sample of size 9, the mean amount of pizza consumed is more than 5 pizzas per person? Probability =
in a recent survey of high school students it was found that the average amount of...
in a recent survey of high school students it was found that the average amount of money spent on entertainment each week was normally distributed with a mean of $52.30 and a standard deviation of$18.23. Assuming these values are represented of all high school students, what is the probability that for a sample of 25, the average amount sent by each student exceeds $60? a)0.3372 b)0.1628 c)0.4826 d)0.0174
A recent national survey found that high school students watched an average (mean) of 7.2 DVDs...
A recent national survey found that high school students watched an average (mean) of 7.2 DVDs per month with a population standard deviation of 0.90 hour. The distribution of DVDs watched per month follows the normal distribution. A random sample of 35 college students revealed that the mean number of DVDs watched last month was 6.20. At the 0.05 significance level, can we conclude that college students watch fewer DVDs a month than high school students? b. State the decision...
In​ 2008, the per capita consumption of soft drinks in Country A was reported to be...
In​ 2008, the per capita consumption of soft drinks in Country A was reported to be 18.44 gallons. Assume that the per capita consumption of soft drinks in Country A is approximately normally​ distributed, with a mean of 18.44 gallons and a standard deviation of 55 gallons. Complete parts​ (a) through​ (d) below. a. What is the probability that someone in Country A consumed more than 12 gallons of soft drinks in​ 2008? The probability is ​(Round to four decimal...
A recent national survey found that high school students watched an average (mean) of 7.2 DVDs...
A recent national survey found that high school students watched an average (mean) of 7.2 DVDs per month with a population standard deviation of 0.90 hour. The distribution of DVDs watched per month follows the normal distribution. A random sample of 35 college students revealed that the mean number of DVDs watched last month was 6.20. At the 0.05 significance level, can we conclude that college students watch fewer DVDs a month than high school students? d. What is your...
In​ 2008, the per capita consumption of soft drinks in Country A was reported to be...
In​ 2008, the per capita consumption of soft drinks in Country A was reported to be 18.97 gallons. Assume that the per capita consumption of soft drinks in Country A is approximately normally​ distributed, with a mean of 18.97 gallons and a standard deviation of 5 gallons. Complete parts​ (a) through​ (d) below. a. What is the probability that someone in Country A consumed more than 12 gallons of soft drinks in​ 2008? The probability is ​(Round to four decimal...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT