A certain tennis player makes a successful first serve 74% of the time. Suppose the tennis player serves 110 times in a match. What's the probability that she makes at least 86 first serves?
In: Statistics and Probability
Suppose you run a regression containing observations for each of
the 74 kinds of cars released in 1978 in the United States, and you
regress price (in dollars) on weight (in pounds). You get the
following results:
ˆ β0 is -6.71, with SE 1174.4. ˆ β1 (slope coefficient on weight) is
2.04 with SE .377.
• (a) Say, in words, what the slope coefficient means in this case,
without taking a stand on causality.
• (b) Suppose I give you the following information: the sum of squares total is roughly equal to 635 million, and the sum of squares explained is equal to 185 million. Please report the R2 and the correlation coefficient between price and weight.
• (c) Use your regression model to predict what the price would be for a car that weighs 3000 pounds.
• (d) Use the SER to add uncertainty and make this prediction an
interval. • (5 points) Build a 95% confidence interval for the slope
coefficient and report the p-value for comparing it to 0. Interpret
your results.
In: Statistics and Probability
Approximate the measures of center for following GFDT.
| Data | Frequency |
|---|---|
| 70 - 74 | 2 |
| 75 - 79 | 1 |
| 80 - 84 | 3 |
| 85 - 89 | 3 |
| 90 - 94 | 6 |
| 95 - 99 | 12 |
| 100 - 104 | 13 |
| 105 - 109 | 20 |
| 110 - 114 | 15 |
mode =
median =
mean =
Report mode and median accurate to one decimal place. Report the
mean accurate to two decimal places (or enter as a fraction).
In: Statistics and Probability
Consider the following hypotheses:
H0: μ ≥ 208
HA: μ < 208
A sample of 74 observations results in a sample mean of 202. The
population standard deviation is known to be 26. (You may
find it useful to reference the appropriate table: z table
or t table)
a-1. Calculate the value of the test statistic.
(Negative value should be indicated by a minus sign. Round
intermediate calculations to at least 4 decimal places and final
answer to 2 decimal places.)
a-2. Find the p-value.
p-value < 0.01
b. Does the above sample evidence enable us to
reject the null hypothesis at α = 0.10?
Yes since the p-value is less than the significance level.
No since the p-value is greater than the significance level.
No since the p-value is less than the significance level.
Yes since the p-value is greater than the significance level.
c. Does the above sample evidence enable us to
reject the null hypothesis at α = 0.01?
No since the p-value is greater than the significance level.
No since the p-value is less than the significance level.
Yes since the p-value is greater than the significance level.
Yes since the p-value is less than the significance level.
d. Interpret the results at α =
0.01.
We cannot conclude that the population mean is less than 208.
We conclude that the population mean is less than 208.
We conclude that the population proportion differs from 208.
We conclude that the population proportion equals 208.
In: Statistics and Probability
From a box of fruit containing 74 oranges and 1 apple a random sample of 2 pieces of fruit has been selected without replacement. Let X be the number of oranges and Y be the number of apples in the sample. What will the expected value of X, E(X)?
In: Statistics and Probability
A study finds that graduate students send a mean of 74 text messages per day with a standard deviation of 15.2 text message per day while undergraduate students send a mean of 116 text messages per day with a standard deviation of 26.51. Which group, the undergraduate students or the graduate students have more variation in the number of sent text messages?
|
Undergraduates, because their standard deviation is higher |
||
|
Undergraduates, because their standard deviation is lower |
||
|
Graduate students, because their standard deviation is higher |
||
|
Graduate students, because their standard deviation is lower |
Lenny is an elementary school principal. He's concerned about how the families at his school are doing currently, so he creates a list of questions to ask some of them to get an idea of how they're holding up.
Match each scenario below with the correct sampling technique.
|
| A. |
systematic sample |
| B. |
stratified sample |
| C. |
simple random sample |
| D. |
that's actually the population |
| E. |
convenience sample |
In: Statistics and Probability
The tires of a car make 74 revolutions as the car reduces its speed uniformly from 87.0 km/h to 65.0 km/h. The tires have a diameter of 0.82 m.
What was the angular acceleration of the tires?
If the car continues to decelerate at this rate, how much more time is required for it to stop?
If the car continues to decelerate at this rate, how far does it go? Find the total distance.
In: Physics
1. Find the quotient and remainder when 74 is divided by 13.
2. Use the Euclidean Algorithm to find the GCD of 201 and 111.
3. Express your answer to #2 as a combination of 201 and 111.
4. In Z7 compute the following: a. 4+6, b. 4. 6, c. 35.
In: Advanced Math
In: Nursing
2. The blood groups of 200 people is distributed as follows: 74 type A, 26 type B, 88 type O, and 12 type AB. With this information, answer the following four (3) questions.
Please leave answers to four (4) decimal places!
a. What is the probability of randomly selecting a person has O blood type or AB blood type out of the blood group? (1 point)
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b. What is the probability of selecting out two consecutive people have B blood type in a row (with replacement)? (1 point)
c. What is the probability of selecting out a person has A blood type and afterwards selecting out another person has B blood type out of the blood group (without replacement)? (1 point)
In: Statistics and Probability