Felicia buys 3-ring binders in the school shop for her classes. The cost of 20 binders is $40.

An army base in the desert is located at the origin, O of an x-y coordinate system. A soldier at point P needs to determine his

Nutka1998 [239]

Answer/step-by-step explanation

The soldier at point P lie on a parabola because he determined his position and distances from towns A and B through measurement of the difference in timing (phase) of radio signals received from the two towns.

This analysis of the signal time difference gives the difference in distance of the soldier at P, from the towns.

This process is known as hyperbolic navigation.

These distances of point P from towns A and B is estimated by the soldier at point P, by measuring the delay localizes the receiver to a hyperbolic line on a chart.

Two hyperbolic lines will be drawn by taking timing measurements from the

towns A and B .

Point P will be at the intersection of the lines.

These distances of point P(The soldier's positions) from town A and town B were determined using the timing of the signals received from the two towns, due to the fact that point P was on a certain hyperbola.

8 0

3 years ago

Suppose the standard deviation of a normal population is known to be 3, and H0 asserts that the mean is equal to 12. A random sa

blagie [28]

Answer:

$z=\frac{12.95-12}{\frac{3}{\sqrt{36}}}=1.9$

$p_v =P(z>1.9)=0.0287$

If we compare the p value and the significance level given $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the true mean is higher than 12 at 5% of signficance.

Step-by-step explanation:

Data given and notation

$\bar X=12.95$ represent the sample mean

$\sigma=3$ represent the population standard deviation for the sample

$n=36$ sample size

$\mu_o =12$ represent the value that we want to test

$\alpha=0.05$ represent the significance level for the hypothesis test.

z would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the mean is equal to 12, the system of hypothesis would be:

Null hypothesis: $\mu \leq 12$

Alternative hypothesis: $\mu > 12$

Since we know the population deviation, is better apply a z test to compare the actual mean to the reference value, and the statistic is given by:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

z-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$z=\frac{12.95-12}{\frac{3}{\sqrt{36}}}=1.9$

P-value

Since is a right tailed test the p value would be:

$p_v =P(z>1.9)=0.0287$

Conclusion

If we compare the p value and the significance level given $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the true mean is higher than 12 at 5% of signficance.

4 0

3 years ago

Read 2 more answers

Samantha and Luis are attempting to determine the average number of library books that seventh-grade students check out at one t

postnew [5]

Answer:

A

Step-by-step explanation:

Luis because the sample is taken from the population of all seventh graders.

6 0

3 years ago

Read 2 more answers

What happens to infrared radiation released by the Earth if there is an increased level of carbon dioxide in the atmosphere? (1

motikmotik

Answer: It is absorbed and heats the atmosphere.

Step-by-step explanation: it's absorbed and emitted back toward Earth's surface.

5 0

2 years ago

A skier is trying to decide whether or not to buy a season ski pass. A daily pass costs $65. A season pass costs $400. The skier

Vlad [161]

Let x be the number of days.

Daily pass:
65x + 30x
95x

Season pass:
400 + 30x

95x > 400 + 30x
65x > 400
x > 6.15

The number of days can't be 6.15, so you must round. You can't go down because then the price will be more expensive, so you have to round up.

It would take 7 days until the season pass is less expensive than the daily pass.
----------------------
You can check this by plugging in the x.

95x > 400 + 30x
95(7) > 400 + 30(7)
665 > 400 + 210
665 > 600
The daily pass is more expensive than the season pass.

3 0

3 years ago