A new car that is a gas- and electric-powered hybrid has recently hit the market. The distance travelled on 1 gallon of fuel is normally distributed with a mean of 50 miles and a standard deviation of 8 miles. Find the probability of the following events:
A. The car travels more than 55 miles per gallon. Probability =
B. The car travels less than 47 miles per gallon. Probability =
C. The car travels between 42 and 53 miles per gallon. Probability =
In: Statistics and Probability
A new car that is a gas- and electric-powered hybrid has recently hit the market. The distance traveled on 1 gallon of fuel is normally distributed with a mean of 45 miles and a standard deviation of 7 miles. Find the probability of the following events:
A. The car travels more than 53 miles per gallon.
Probability =
B. The car travels less than 42 miles per gallon.
Probability =
C. The car travels between 39 and 52 miles per gallon.
Probability =
In: Statistics and Probability
A new car that is a gas- and electric-powered hybrid has recently hit the market. The distance travelled on 1 gallon of fuel is normally distributed with a mean of 55 miles and a standard deviation of 6 miles. Find the probability of the following events:
A. The car travels more than 59 miles per gallon.
Probability =
B. The car travels less than 51 miles per gallon.
Probability =
C. The car travels between 50 and 63 miles per gallon.
Probability =
In: Statistics and Probability
A new car that is a gas- and electric-powered hybrid has recently hit the market. The distance travelled on 1 gallon of fuel is normally distributed with a mean of 50 miles and a standard deviation of 8 miles. Find the probability of the following events:
A. The car travels more than 54 miles per gallon.
Probability =
B. The car travels less than 42 miles per gallon.
Probability =
C. The car travels between 44 and 57 miles per gallon.
Probability =
In: Statistics and Probability
A new car that is a gas- and electric-powered hybrid has recently hit the market. The distance travelled on 1 gallon of fuel is normally distributed with a mean of 45 miles and a standard deviation of 7 miles. Find the probability of the following events:
A. The car travels more than 50 miles per gallon.
Probability =
B. The car travels less than 40 miles per gallon.
Probability =
C. The car travels between 37 and 51 miles per gallon.
Probability =
In: Statistics and Probability
|
In 2008, a small dealership leased 21 Subaru Outbacks on 2-year leases. When the cars were returned in 2010, the mileage was recorded (see below). |
| 40,003 | 24,939 | 14,329 | 17,380 | 44,741 | 44,554 | 20,229 |
| 33,370 | 24,220 | 41,702 | 58,328 | 35,831 | 25,790 | 28,983 |
| 25,066 | 43,357 | 23,993 | 43,557 | 53,670 | 31,811 | 36,709 |
| (a) |
Is the dealer's mean significantly greater than the national average of 30,162 miles for 2-year leases? Using the 10 percent level of significance, choose the appropriate hypothesis. |
| a. | H0: μ ≤ 30,162 miles vs. H1: μ > 30,162 miles, reject H0 if tcalc > 1.3250 |
| b. | H0: μ ≥ 30,162 miles vs. H1: μ > 30,162 miles, reject H0 if tcalc > 1.3250 |
| c. | H0: μ ≤ 30,162 miles vs. H1: μ < 30,162 miles, reject H0 if tcalc > 1.3250 |
| d. | H1: μ ≤ 30,162 miles vs. H0: μ > 30,162 miles, reject H0 if tcalc > 1.3250 |
|
| (b) |
Calculate the test statistic. (Round your answer to 2 decimal places.) |
| Test statistic |
| (c) |
The dealer's cars show a significantly greater mean number of miles than the national average at the 10 percent level. |
|
In: Statistics and Probability
|
In 2008, a small dealership leased 21 Subaru Outbacks on 2-year leases. When the cars were returned in 2010, the mileage was recorded (see below). |
| 40,003 | 24,939 | 14,329 | 17,380 | 44,741 | 44,554 | 20,229 |
| 33,370 | 24,220 | 41,702 | 58,328 | 35,831 | 25,790 | 28,983 |
| 25,066 | 43,357 | 23,993 | 43,557 | 53,670 | 31,811 | 36,709 |
| (a) |
Is the dealer's mean significantly greater than the national average of 30,162 miles for 2-year leases? Using the 10 percent level of significance, choose the appropriate hypothesis. |
| a. | H0: μ ≤ 30,162 miles vs. H1: μ > 30,162 miles, reject H0 if tcalc > 1.3250 |
| b. | H0: μ ≥ 30,162 miles vs. H1: μ > 30,162 miles, reject H0 if tcalc > 1.3250 |
| c. | H0: μ ≤ 30,162 miles vs. H1: μ < 30,162 miles, reject H0 if tcalc > 1.3250 |
| d. | H1: μ ≤ 30,162 miles vs. H0: μ > 30,162 miles, reject H0 if tcalc > 1.3250 |
|
| (b) |
Calculate the test statistic. (Round your answer to 2 decimal places.) |
| Test statistic |
| (c) |
The dealer's cars show a significantly greater mean number of miles than the national average at the 10 percent level. |
|
In: Statistics and Probability
The lifetime of a particular brand of tire is modeled with a normal distribution with mean μ = 75,000 miles and standard deviation σ = 5,000 miles.
a) What is the probability that a randomly selected tire lasts less than 67,000 miles?
b) If a random sample of 35 tires is taken, what is the probability that the sample mean is greater than 70,000 miles?
In: Statistics and Probability
The head of maintenance at XYZ Rent-A-Car believes that the mean number of miles between services is 2643 miles, with a standard deviation of 368 miles. If he is correct, what is the probability that the mean of a sample of 44 cars would differ from the population mean by less than 51 miles? Round your answer to four decimal places.
In: Math
A metropolitan transportation authority has set a bus mechanical reliability goal of 3,700 bus miles. Bus mechanical reliability is measured specifically as the number of bus miles between mechanical road calls. Suppose a sample of 100 buses resulted in a sample mean of 3,775 bus miles and a sample standard deviation of 325 bus miles.
a. Is there evidence that the population mean bus miles is more than 3,700 bus miles? (Use a 0.10 level of significance.) State the null and alternative hypotheses.
b. Find the test statistic for this hypothesis test.
c. The critical value(s) for this test statistic is(are)
d. Determine the p-value and interpret its meaning.
In: Statistics and Probability