Please help me with this

Alice is riding a Ferris wheel, where t is time in seconds. Suppose the Ferris wheel is 22 m tall. Let h(t) = 11cos(12t) represe

Soloha48 [4]

Answer:

Alice reaches 11 metres below the centre as lowest height.

Step-by-step explanation:

Cosine is a bounded function between -1 and 1, so that the lowest height that Alice achieves in Ferris wheel is:

$h(t) = 11\cdot \cos (12\cdot t)$

Where:

$t$ - Time, measured in seconds.

$h(t)$ - Height with respect to centre, measured in metres.

If $\cos (12\cdot t) = -1$ , then:

$h_{min} = 11\cdot (-1)$

$h_{min} = -11\,m$

Alice reaches 11 metres below the centre as lowest height.

7 0

2 years ago

4. Priya is teaching her younger cousin to ride a bike. She wants to stay on roads that are not too steep and easy enough for a

taurus [48]

Answer:

Having 2 meters and 25 meters legs and 3 meters and 30 meters legs.

Step-by-step explanation:

Priya thinks that an angle of elevation of 7 Degrees or less will be safe for a learner of bike riding.

Now, a 7-degree elevation angle in a right triangle will have a 3 : 25 ratio of its legs.

Therefore, the list of 2 right triangles that would be safe for a new rider will be having 2 meters and 25 meters legs and 3 meters and 30 meters legs.

I both cases the angle of elevation will be less than 7 degrees. (Answer)

4 0

2 years ago

The results of a mathematics placement exam at two different campuses of Mercy College follow: Campus Sample Size Sample Mean Po

Leona [35]

Answer:

$z=\frac{(33-31)-0}{\sqrt{\frac{8^2}{330}+\frac{7^2}{310}}}}=3.37$

$p_v =P(Z>3.37)=1-P(Z$

Comparing the p value with a significance level for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say that the mean for the Campus 1 is significantly higher than the mean for the group 2.

Step-by-step explanation:

Data given

Campus Sample size Mean Population deviation

1 330 33 8

2 310 31 7

$\bar X_{1}=33$ represent the mean for sample 1

$\bar X_{2}=31$ represent the mean for sample 2

$\sigma_{1}=8$ represent the population standard deviation for 1

$\sigma_{2}=7$ represent the population standard deviation for 2

$n_{1}=330$ sample size for the group 1

$n_{2}=310$ sample size for the group 2

$\alpha$ Significance level provided

z would represent the statistic (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to check if the mean for Campus 1 is higher than the mean for Campus 2, the system of hypothesis would be:

Null hypothesis: $\mu_{1}-\mu_{2}\leq 0$

Alternative hypothesis: $\mu_{1} - \mu_{2}> 0$

We have the population standard deviation's, and the sample sizes are large enough we can apply a z test to compare means, and the statistic is given by:

$z=\frac{(\bar X_{1}-\bar X_{2})-\Delta}{\sqrt{\frac{\sigma^2_{1}}{n_{1}}+\frac{\sigma^2_{2}}{n_{2}}}}$ (1)

z-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

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

$z=\frac{(33-31)-0}{\sqrt{\frac{8^2}{330}+\frac{7^2}{310}}}}=3.37$

P value

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

$p_v =P(Z>3.37)=1-P(Z$

Comparing the p value with a significance level for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say that the mean for the Campus 1 is significantly higher than the mean for the group 2.

5 0

2 years ago

A and B will take the same 10-question examination. Each question will be answered correctly by A with probability .7, independe

MatroZZZ [7]

Answer:

a) The expected number of questions that are answered correctly by both A and B = 11 (7 + 4).

b) The Variance of the number of questions that are answered correctly by either A or B = 2.25.

Step-by-step explanation:

Number of questions in the examination = 10

Probability of A's answer being correct = 0.7

Probability of B's answer being correct = 0.4

The expected number of questions that are answered correctly by both A and B:

Probability of Expected

Correct Answer Value Variance

A 0.7 7 (0.7 * 10) 2.25

B 0.4 4 (0.4 * 10) 2.25

Total expected value = 11

Mean = 5.5 2.25

5 0

2 years ago

Manuel painted 0.75 of a rectangular banner green. After the paint dried, he painted 0.6 of the green area orange. What part of

NNADVOKAT [17]

Answer:

0.45 part of the banner is painted orange

Step-by-step explanation:

portion of rectangular banner painted green = 0.75

Portion of green painted part which is now painted orange = 0.60

Hence we can say that

0.6 part out of 0.75 part of total banner is painted orange

mathematically it is

0.6 * 0.75 = 0.45

Thus 0.45 part of banner is painted orange .

6 0

2 years ago