All categories

2 years ago

Martina begins a dive at sea level. She dives down 20 feet, and then rises 7 feet.

Mathematics

1 answer:

klasskru [66]2 years ago

3 0

Answer:

martina is 22 feet below sea level

Step-by-step explanation:

Marina goes down 20 feet

then rises 7 feet which is 20 - 7 = 13

then goes down 9 more feet which is 13 + 9 = 22 feet

20 - 7 + 9 =22

Martina is 22 feet below sea level.

You might be interested in

At 95% confidence, how large a sample should be taken to obtain a margin of error of 0.03 for the estimation of a population pro

Gnom [1K]

Answer:

A sample of 1068 is needed.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

The margin of error is:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a pvalue of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

At 95% confidence, how large a sample should be taken to obtain a margin of error of 0.03 for the estimation of a population proportion?

We need a sample of n.

n is found when M = 0.03.

We have no prior estimate of $\pi$ , so we use the worst case scenario, which is $\pi = 0.5$

Then

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

$0.03 = 1.96\sqrt{\frac{0.5*0.5}{n}}$

$0.03\sqrt{n} = 1.96*0.5$

$\sqrt{n} = \frac{1.96*0.5}{0.03}$

$(\sqrt{n})^{2} = (\frac{1.96*0.5}{0.03})^{2}$

$n = 1067.11$

Rounding up

A sample of 1068 is needed.

8 0

3 years ago

Plz help if you can<br> Thank ya

koban [17]

Answer:

$90\pi$

Step-by-step explanation:

The first step is to find the slant height of the cone. Using the pythagorean theorem, you can find that $\sqrt{12^2+5^2}=13$ cm. Plugging this into the equation, you get $\pi \cdot 5 \cdot 13=90\pi$ . Hope this helps!

3 0

3 years ago

This is hard please help it makes no sense

tigry1 [53]

Answer:

lk12

Step-by-step explanation:

3 0

2 years ago

Read 2 more answers

Which of the following could NOT

Mama L [17]

Answer:

Step-by-step explanation:

|-12|= 12

this means that it represents a positive number. Each answer represents a positive number other than the town that lies -12 feet below sea level. (sorry if I'm wrong)

6 0

3 years ago

QUICK HELP!!!!

sasho [114]

Answer:

$y = \frac{3}{4} x - \frac{3}{2}$