Answer:
first off where is the photo
Answer:
The probability that the child must wait between 6 and 9 minutes on the bus stop on a given morning is 0.148.
Step-by-step explanation:
Let the random variable <em>X</em> represent the time a child spends waiting at for the bus as a school bus stop.
The random variable <em>X</em> is exponentially distributed with mean 7 minutes.
Then the parameter of the distribution is,
.
The probability density function of <em>X</em> is:

Compute the probability that the child must wait between 6 and 9 minutes on the bus stop on a given morning as follows:

![=\int\limits^{9}_{6} {\frac{1}{7}\cdot e^{-\frac{1}{7} \cdot x}} \, dx \\\\=\frac{1}{7}\cdot \int\limits^{9}_{6} {e^{-\frac{1}{7} \cdot x}} \, dx \\\\=[-e^{-\frac{1}{7} \cdot x}]^{9}_{6}\\\\=e^{-\frac{1}{7} \cdot 6}-e^{-\frac{1}{7} \cdot 9}\\\\=0.424373-0.276453\\\\=0.14792\\\\\approx 0.148](https://tex.z-dn.net/?f=%3D%5Cint%5Climits%5E%7B9%7D_%7B6%7D%20%7B%5Cfrac%7B1%7D%7B7%7D%5Ccdot%20e%5E%7B-%5Cfrac%7B1%7D%7B7%7D%20%5Ccdot%20x%7D%7D%20%5C%2C%20dx%20%5C%5C%5C%5C%3D%5Cfrac%7B1%7D%7B7%7D%5Ccdot%20%5Cint%5Climits%5E%7B9%7D_%7B6%7D%20%7Be%5E%7B-%5Cfrac%7B1%7D%7B7%7D%20%5Ccdot%20x%7D%7D%20%5C%2C%20dx%20%5C%5C%5C%5C%3D%5B-e%5E%7B-%5Cfrac%7B1%7D%7B7%7D%20%5Ccdot%20x%7D%5D%5E%7B9%7D_%7B6%7D%5C%5C%5C%5C%3De%5E%7B-%5Cfrac%7B1%7D%7B7%7D%20%5Ccdot%206%7D-e%5E%7B-%5Cfrac%7B1%7D%7B7%7D%20%5Ccdot%209%7D%5C%5C%5C%5C%3D0.424373-0.276453%5C%5C%5C%5C%3D0.14792%5C%5C%5C%5C%5Capprox%200.148)
Thus, the probability that the child must wait between 6 and 9 minutes on the bus stop on a given morning is 0.148.
Answer:
A = 50
Step-by-step explanation:
The sum of the angles of a triangle is 180 degrees
A+B+C =180
2x-10 + 70 + x+30 = 180
Combine like terms
3x +90 = 180
Subtract 90 from each side
3x +90-90 = 180-90
3x= 90
Divide each side by 3
3x/3=90/3
x =30
We want to find A
A =2x-10
= 2*30 -10
=60-10
=50
Step-by-step explanation:
![\sqrt{p} = \sqrt[r]{w - {as}^{2} }](https://tex.z-dn.net/?f=%20%5Csqrt%7Bp%7D%20%20%3D%20%20%5Csqrt%5Br%5D%7Bw%20-%20%20%7Bas%7D%5E%7B2%7D%20%7D%20)
Find raise each side of the expression to the power of r
That's
<h2>
![( \sqrt{p} )^{r} = (\sqrt[r]{w - {as}^{2} } ) ^{r}](https://tex.z-dn.net/?f=%28%20%5Csqrt%7Bp%7D%20%29%5E%7Br%7D%20%20%3D%20%20%28%5Csqrt%5Br%5D%7Bw%20-%20%20%7Bas%7D%5E%7B2%7D%20%7D%20%29%20%5E%7Br%7D%20)
</h2>
we have
<h2>

</h2>
Send w to the left of the equation
<h2>

</h2>
Divide both sides by - a
We have
<h2>

</h2>
Find the square root of both sides
We have the final answer as
<h2>

</h2>
Hope this helps you
Answer:Second Step
Step-by-step explanation:
On the right side in step two you added -3b-15b, and ended up with -12b. This is incorrect. -3b-15b is actually -18b