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2 years ago

2\r=1/r-1/r+3 what's the answer?

2 answers:

6 0

$\frac{2}{r} = \frac{1}{r} -\frac{1}{r}+3\ \ \ and\ \ \ r \neq 0\\\\ \frac{2}{r} =3\ /\cdot r\\\\2=3r\ /:3\\\\ \frac{2}{3} =r$

Andre45 [30]2 years ago

4 0

$\frac{2}{r}=\frac{1}{r}-\frac{1}{r+3};\ D:r\neq0\ \wedge\ r\neq-3\\\\\frac{2}{r}-\frac{1}{r}=\frac{-1}{r+3}\\\\\frac{1}{r}=\frac{-1}{r+3}\\\\cross\ multiply\\\\r+3=-r\\\\r+r=-3\\\\2r=-3\\\\\boxed{r=-1.5}$

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Complete the chart to find the mean, variance, and standard deviation. Remember to use commas and round numbers to the nearest t

vitfil [10]

Answer: The mean of the data is 433.75, variance of the data is 99667.19 and the standard deviation of the data is 315.7011.

Explanation:

The given data is 900, 35, 500 and 300.

The number of observation is 4.

Formula of mean is,

$\text{Mean}=\frac{\text{Sum of observations}}{\text{Number of observations}}$

$\bar{X}=\frac{900+35+50+300}{4} =433.75$

The formula of variance is given below,

$\sigma^2=\frac{1}{n}\sum{(X-\bar{X})^2}$

$\sigma^2=\frac{398668.75}{4}$

$\sigma^2=99667.19$

The variance of the data is 99667.19

$\sigma=\sqrt{99667.19}$

$\sigma=315.7011$

The standard deviation of the data is 315.7011.

The other information or values of given chart is shown in the attached table.

8 0

2 years ago

Read 2 more answers

The lifespans of gorillas in a particular zoo are normally distributed. the average gorilla lives 20.8 years; the standard devia

dezoksy [38]

Answer:

Step-by-step explanation: 2.35%+95%

Answer is 97.35%

5 0

3 years ago

Write an equation of the line that passes through the points (-2,-2) and (0,5)

marshall27 [118]

$\bf \begin{array}{ccccccccc}
&&x_1&&y_1&&x_2&&y_2\\
&&(~ -2 &,& -2~) 
&&(~ 0 &,& 5~)
\end{array}
\\\\\\
% slope = m
slope = m\implies 
\cfrac{\stackrel{rise}{ y_2- y_1}}{\stackrel{run}{ x_2- x_1}}\implies \cfrac{5-(-2)}{0-(-2)}\implies \cfrac{5+2}{0+2}\implies \cfrac{7}{2}
\\\\\\
\stackrel{\textit{point-slope form}}{y- y_1= m(x- x_1)}\implies y-(-2)=\cfrac{7}{2}[x-(-2)]
\\\\\\
y+2=\cfrac{7}{2}(x+2)\implies y+2=\cfrac{7}{2}x+7\implies y=\cfrac{7}{2}x+5$

3 0

2 years ago

The function h(t) = -16t^2 + 16t represents the height (in feet) of a horse (t) seconds after it jumps during a steeplechase.

Vladimir79 [104]

A.) To find the maximum height, we can take the derivative of h(t). This will give us the rate at which the horse jumps (velocity) at time t.

h'(t) = -32t + 16

When the horse reaches its maximum height, its position on h(t) will be at the top of the parabola. The slope at this point will be zero because the line tangent to the peak of a parabola is a horizontal line. By setting h'(t) equal to 0, we can find the critical numbers which will be the maximum and minimum t values.

-32t + 16 = 0

-32t = -16

t = 0.5 seconds

b.) To find out if the horse can clear a fence that is 3.5 feet tall, we can plug 0.5 in for t in h(t) and solve for the maximum height.

h(0.5) = -16(0.5)^2 + 16(-0.5) = 4 feet

If 4 is the maximum height the horse can jump, then yes, it can clear a 3.5 foot tall fence.

c.) We know that the horse is in the air whenever h(t) is greater than 0.

-16t^2 + 16t = 0

-16t(t-1)=0

t = 0 and 1

So if the horse is on the ground at t = 0 and t = 1, then we know it was in the air for 1 second.

7 0

2 years ago

A weather forecaster says the temperature will be about-5C “give or take” 10 degrees. What is the greatest possible temperature?

IRINA_888 [86]

The greatest possible temperature is $5^{\circ} \mathrm{C}$ and least possible temperature is $-15^{\circ} \mathrm{C}$

<u>Solution:</u>

Given that according to weather forecaster the temperature will be about -5 degree celsius given or take 10 degree”

Need to determine greatest possible temperature and least possible temperature.

Give and take in given statement means a temperature can go up by 10 degrees and can go down by 10 degrees

So greatest possible temperature will be $-5^{\circ} \mathrm{C}+10^{\circ} \mathrm{C}=5^{\circ} \mathrm{C}$

Least possible temperature will be $-5^{\circ} \mathrm{C}-10^{\circ} \mathrm{C}=-15^{\circ} \mathrm{C}$

Hence according to weather forecaster, greatest possible temperature = $5^{\circ} \mathrm{C}$ and least possible temperature = $-15^{\circ} \mathrm{C}$

4 0

2 years ago