Question

In: Statistics and Probability

#3 – Suppose a random sample of text-message lengths (in characters) resulted in the following observations:...

#3 – Suppose a random sample of text-message lengths (in characters) resulted in the following observations: 59,60,52,66,73. What was the sample’s standard deviation?

ANSWER:

#5 – In a marketing study participant were measured as to: 1) the number of mobile devices registered to their wireless plan; and 2) the amount of data (in average GB per month) they use. The first measurement would result in _____ data and the second measurement would result in _____ data.

ANSWER:

#6 – Pat was among 170 college students participating in a quantitative skills assessment. It has been determined that there were 34 scores that were lower than Pat’s. Pat’s score therefore was the _____ percentile.

ANSWER:

#8 – For a given population, the mean is equal to 65 and the standard deviation equal to 10. An observation from this population with a standardized value of

Z = -13 would have an actual value of _______.

ANSWER:

Solutions

Expert Solution

Result:

#3 – Suppose a random sample of text-message lengths (in characters) resulted in the following observations: 59,60,52,66,73. What was the sample’s standard deviation?

ANSWER: 7.9057

n

5

sum

310.00

sum of squares

19,470.00

= 7.9057

#5 – In a marketing study participant were measured as to: 1) the number of mobile devices registered to their wireless plan; and 2) the amount of data (in average GB per month) they use. The first measurement would result in discrete data and the second measurement would result in continuous data.

ANSWER: discrete, continuous

#6 – Pat was among 170 college students participating in a quantitative skills assessment. It has been determined that there were 34 scores that were lower than Pat’s. Pat’s score therefore was the _____ percentile.

ANSWER:19.54

(34/174)*100 =19.54023

#8 – For a given population, the mean is equal to 65 and the standard deviation equal to 10. An observation from this population with a standardized value of

Z = -13 would have an actual value of _______.

ANSWER: 52

Let given z value -1.3

X= mean+z*sd = 65-1.3*10

= 52


Related Solutions

A random sample of n​ = 7 observations from a normal distribution resulted in the data...
A random sample of n​ = 7 observations from a normal distribution resulted in the data shown in the table. Compute a 90​% confidence interval for sigma squared. 91 99 106 95 84 69 84
The lengths of text messages are normally distributed with a population standard deviation of 5 characters...
The lengths of text messages are normally distributed with a population standard deviation of 5 characters and an unknown population mean. If a random sample of 21 text messages is taken and results in a sample mean of 28 characters, find a 99% confidence interval for the population mean. Round your answers to two decimal places.
The lengths of text messages are normally distributed with a population standard deviation of 4 characters...
The lengths of text messages are normally distributed with a population standard deviation of 4 characters and an unknown population mean. If a random sample of 24 text messages is taken and results in a sample mean of 30 characters, find a 95% confidence interval for the population mean. Round your answers to two decimal places. z0.10 z0.05 z0.04 z0.025 z0.01 z0.005 1.282 1.645 1.751 1.960 2.326 2.576 You may use a calculator or the common z-values above. Select the...
3. A random sample of 64 lighting flashes in a certain region resulted in a sample...
3. A random sample of 64 lighting flashes in a certain region resulted in a sample average radar echo duration of 0.7 sec and a sample standard deviation of 0.32 sec. • (a) Construct a 89% confidence interval for the true mean radar echo duration. • (b) Explain the meaning of your interval in such a way that someone who had not ever studied statistics would understand. • (c) At a 0.11 level of significance, can you conclude that the...
Suppose a random sample of n = 5 observations is selected from a population that is...
Suppose a random sample of n = 5 observations is selected from a population that is normally distributed, with mean equal to 7 and standard deviation equal to 0.33. (a) Give the mean and standard deviation of the sampling distribution of x. (Round your standard deviation to four decimal places.) mean standard deviation (b) Find the probability that x exceeds 7.3. (Round your answer to four decimal places.) (c) Find the probability that the sample mean x is less than...
Suppose a random sample of n = 16 observations is selected from a population that is...
Suppose a random sample of n = 16 observations is selected from a population that is normally distributed with mean equal to 105 and standard deviation equal to 11. (use SALT) (a) Give the mean and the standard deviation of the sampling distribution of the sample mean x. mean     standard deviation     (b) Find the probability that x exceeds 109. (Round your answer to four decimal places.) (c) Find the probability that the sample mean deviates from the population mean μ...
Suppose a random sample of n = 5 observations is selected from a population that is...
Suppose a random sample of n = 5 observations is selected from a population that is normally distributed, with mean equal to 3 and standard deviation equal to 0.35. (a) Give the mean and standard deviation of the sampling distribution of x. (Round your standard deviation to four decimal places.) (b) Find the probability that x exceeds 3.3. (Round your answer to four decimal places.) (c) Find the probability that the sample mean x is less than 2.5. (Round your...
A random sample of 50 measurements resulted in a sample mean of 62 with a sample...
A random sample of 50 measurements resulted in a sample mean of 62 with a sample standard deviation 8. It is claimed that the true population mean is at least 64. a) Is there sufficient evidence to refute the claim at the 2% level of signifigance? b) What is the p-vaule? c) What is the smallest value of alpha for which the claim will be rejected?
1) Suppose there is a random sample of n observations, divided into four groups. The table...
1) Suppose there is a random sample of n observations, divided into four groups. The table below summarizes the count of observations that were seen in each group. Group 1 Group 2 Group 3 Group 4 16 46 51 37 We are interested in testing the null hypothesis H0:p1=p2=p3=p4=0.25, against the alternative hypothesis HA: At least one proportion is incorrect a) What is the expected count for each of the groups? Expected: (number) b) What is the value of the...
Suppose there is a random sample of 1,083 observations, divided into four groups. The table below...
Suppose there is a random sample of 1,083 observations, divided into four groups. The table below summarizes the observations that were seen in each group. Group 1 Group 2 Group 3 Group 4 531 184 101 267 We are interested in testing the Null hypothesis Observed=Expected, under the assumption that the expected proportions are .50, .20, .10, and .20 for the 4 groups, respectively. What are the expected values? Group 1 Group 2 Group 3 Group 4 Number Number Number...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT