Substitute the given values into the formula, and solve for the unknown variable.

Mathematics

1 answer:

Step2247 [10]3 years ago

3 0

21=1/2h(2+5)
21=1/2h+7
21
-7
14=1/2h

14 divided by 1/2 equals 28

h=28

You might be interested in

Explain with example of why 2^(-8) * 2^(-7) is equal to 2^(-15)

tatyana61 [14]

(-8)*(-7)=(-15)

the 2 in the beginning stays the same, and you multiply what’s in the parentheses to get (-15)

4 0

3 years ago

Y= sqrt(8 x^3 as it reaches the point (2, 4, the y-coordinate is increasing at a rate of 5 cm/s. how fast is the x-coordinate of

AysviL [449]

Y = √8x³

dy/dt = 2√2 * 3/2 * √x * dx/dt
⇒ 5 = 2√2 * 3/2 * √2 * dx/dt
⇒ 5 = 6 dx/dt
⇒dx/dt = 5/6 cm/s

x coordinate is changing at 5/6 cm/s

Hope it helps!

6 0

3 years ago

If outliers are discarded, then the retirement savings by residents of Econistan is normally distributed with a mean of $100,000

zavuch27 [327]

Answer:

$P(X>117000)=P(\frac{X-\mu}{\sigma}>\frac{117000-\mu}{\sigma})=P(Z>\frac{117000-100000}{20000})=P(z>0.85)$

And we can find this probability using the complement rule and the normal standard table or excel:

$P(z>0.85)=1-P(z$

The firgure attached illustrate the problem

Step-by-step explanation:

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Solution to the problem

Let X the random variable that represent the retirement savings of a population, and for this case we know the distribution for X is given by:

$X \sim N(100000,20000)$

Where $\mu=100000$ and $\sigma=20000$

We are interested on this probability

$P(X>117000)$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

If we apply this formula to our probability we got this:

$P(X>117000)=P(\frac{X-\mu}{\sigma}>\frac{117000-\mu}{\sigma})=P(Z>\frac{117000-100000}{20000})=P(z>0.85)$

And we can find this probability using the complement rule and the normal standard table or excel:

$P(z>0.85)=1-P(z$

The firgure attached illustrate the problem

7 0

3 years ago

Need help on this! Please someone help!!!

Jet001 [13]

This can be easily solved, especially with a calculator.
With the calculator, you can find that $\sqrt{42}$ is about 6.4807.
Multiply that by 2, you get about 13 inches.

If you can't use a calculator, then you can just estimate. Since we know that $\sqrt{36}$ is 6 and $\sqrt{49}$ is 7, $\sqrt{42}$ is in between them, so you can just say somewhere around 6.5.

Multiply 2 * 6.5 and you get 13 inches.