The graph illustrates the distribution of test scores taken by College Algebra students. The maximum possible score on the test was 140, while the mean score was 76 and the standard deviation was 14.
34 48 62 76 90 104 118 Distribution of Test Scores
What is the approximate percentage of students who scored between 62 and 76? %
What is the approximate percentage students who scored between 62 and 90 on the test? %
What is the approximate percentage of students who scored between 76 and 118 on the test? %
What is the approximate percentage of students who scored between 48 and 104 on the test? %
In: Statistics and Probability
The ages of commercial aircraft are normally distributed with a mean of 13.5 years and a standard deviation of 8.3693 years. What percentage of individual aircraft have ages between 9 years and 16 years? Assume that a random sample of 49 aircraft is selected and the mean age of the sample is computed. What percentage of sample means have ages between 9 years and 16 years?
The percentage of individual aircraft that have ages between 9 years and 16 years is 32.
The percentage of sample means that have ages between 9 years and 16 years is nothing %. (Round to the nearest tenth as needed.)
In: Statistics and Probability
You are the operations manager for an airline and you are considering a higher fare level for passengers in aisle seats. How many randomly selected air passengers must you survey? Assume that you want to be 90% confident that the sample percentage is within 4.5 percentage points of the true population percentage. Complete parts (a) and (b) below.
.a. Assume that nothing is known about the percentage of passengers who prefer aisle seats.
n=?
(Round up to the nearest integer.)
b. Assume that a prior survey suggests that about 36% of air passengers prefer an aisle seat.
n=?
(Round up to the nearest integer.)
In: Statistics and Probability
In: Statistics and Probability
OceanGate sells external hard drives for $400 each. Its total fixed costs are $60 million, and its variable costs per unit are $240. The corporate tax rate is 30%. If the economy is strong, the firm will sell 4 million drives, but if there is a recession, it will sell only half as many.
a. What will be the percentage decline in sales if the economy enters a recession?
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b. What will be the percentage decline in profits if the economy enters a recession?
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c. Comparing your answers to (a) and (b), how would you measure the operating leverage of this firm?
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In: Finance
Not everyone pays the same price for the same model of a new car. Prices paid for a particular model of a new car take on a normal distribution. The mean is $17,000 and the standard deviation is $500. Start by drawing a picture of the normal distribution and then labeling this information.
a. What percentage of buyer paid between $16,000 and $18,000 for a new car?
b. What percentage of buyer paid between $17,000 and $18,000 for a new car?
c. What percentage of buyer paid between $16,500and $17,000 for a new car?
d. What percentage of buyer paid between $17,000 and $18,500 for a new car?
In: Statistics and Probability
You are the operations manager for an airline and you are considering a higher fare level for passengers in aisle seats. How many randomly selected air passengers must you survey? Assume that you want to be 99% confident that the sample percentage is within 2.5 percentage points of the true population percentage. Complete parts (a) and (b) below.
a. Assume that nothing is known about the percentage of passengers who prefer aisle seats.
___ (Round up to the nearest integer.)
b. Assume that a prior survey suggests that about 31% of air passengers prefer an aisle seat.
___(Round up to the nearest integer.)
In: Statistics and Probability
show your work please
You are the operations manager for American Airlines and you are considering a higher fare level for passengers in aisle seats. You want to estimate the percentage of passengers who now prefer aisle seats. a) How many randomly selected air passengers must you survey? Assume that you want to be 95% confident that the sample percentage is within 2.5 percentage points of the true population percentage. b) Assume that a prior survey suggests that about 38% of air passengers prefer an aisle seat.
final answers:
| a) Sample Size | |
| b) Sample Size | |
| Hypothesis |
In: Statistics and Probability
GEM, Inc., has two bonds outstanding in the market. Both Bond X and Bond Y have 7 percent coupons, make semiannual payments, and are priced at par value. Bond X has 20 years to maturity, whereas Bond Y has 5 years to maturity.
1. If interest rates suddenly rise by 2 percent (percentage points), what is the percentage change in the price of the two bonds?
2. If rates were to suddenly fall by 2 percent (percentage points) instead, what would be the percentage change in the price of the two bonds?
USING EXCEL FORMULAS PLEASE
In: Finance
You are the operations manager for an airline and you are considering a higher fare level for passengers in aisle seats. How many randomly selected air passengers must you survey? Assume that you want to be 99% confident that the sample percentage is within 4.5 percentage points of the true population percentage. Complete parts (a) and (b) below.
a. Assume that nothing is known about the percentage of passengers who prefer aisle seats.
n = ?
(Round up to the nearest integer.)
b. Assume that a prior survey suggests that about 29% of air passengers prefer an aisle seat.
n = ?
(Round up to the nearest integer.)
In: Math