Answer:
The tip of the man shadow moves at the rate of ![\frac{20}{3} ft.sec](https://tex.z-dn.net/?f=%5Cfrac%7B20%7D%7B3%7D%20ft.sec)
Step-by-step explanation:
Let's draw a figure that describes the given situation.
Let "x" be the distance between the man and the pole and "y" be distance between the pole and man's shadows tip point.
Here it forms two similar triangles.
Let's find the distance "y" using proportion.
From the figure, we can form a proportion.
![\frac{y - x}{y} = \frac{6}{15}](https://tex.z-dn.net/?f=%5Cfrac%7By%20-%20x%7D%7By%7D%20%3D%20%5Cfrac%7B6%7D%7B15%7D)
Cross multiplying, we get
15(y -x) = 6y
15y - 15x = 6y
15y - 6y = 15x
9y = 15x
y = ![\frac{15x}{9\\} y = \frac{5x}{3}](https://tex.z-dn.net/?f=%5Cfrac%7B15x%7D%7B9%5C%5C%7D%20y%20%3D%20%5Cfrac%7B5x%7D%7B3%7D)
We need to find rate of change of the shadow. So we need to differentiate y with respect to the time (t).
----(1)
We are given
. Plug in the equation (1), we get
![\frac{dy}{dt} = \frac{5}{3} *4 ft/sect\\= \frac{20}{3} ft/sec](https://tex.z-dn.net/?f=%5Cfrac%7Bdy%7D%7Bdt%7D%20%3D%20%5Cfrac%7B5%7D%7B3%7D%20%2A4%20ft%2Fsect%5C%5C%3D%20%5Cfrac%7B20%7D%7B3%7D%20ft%2Fsec)
Here the distance between the man and the pole 45 ft does not need because we asked to find the how fast the shadow of the man moves.
Answer: Integers and Rational Numbers
Explanation: -2 is an integer because integers include positive an negative numbers. It would not be a whole number or a Naural number because both of those sets only include positive numbers. Here’s a better explanation:
Natural numbers: Natural Numbers are like (1,2,3....). They only include positive numbers. Therefore, -2 does not belong in this category.
Whole Numbers: Whole Numbers are like (0,1,2,3....). They include all the natural numbers with 0. Therefore, -2 does not belong in this set.
Integers: Integers include both positive and negative numbers. They are like (-3,-2,-1,0,1,2,3....). Since they both have positive and negative numbers, -2 would belong in this set.
Rational Numbers: Rational Numbers include ALL the sets that were described. (Natural, Whole, Integer). Since this set also includes positive and negative numbers, -2 would belong in this set.
So, -2 belongs in Integers and Rational Numbers
Hope this helps!
Three hundred forty eight thousand five hundred.
Hope this helps!
Answer:
The dimensions of the can that will minimize the cost are a Radius of 3.17cm and a Height of 12.67cm.
Step-by-step explanation:
Volume of the Cylinder=400 cm³
Volume of a Cylinder=πr²h
Therefore: πr²h=400
![h=\frac{400}{\pi r^2}](https://tex.z-dn.net/?f=h%3D%5Cfrac%7B400%7D%7B%5Cpi%20r%5E2%7D)
Total Surface Area of a Cylinder=2πr²+2πrh
Cost of the materials for the Top and Bottom=0.06 cents per square centimeter
Cost of the materials for the sides=0.03 cents per square centimeter
Cost of the Cylinder=0.06(2πr²)+0.03(2πrh)
C=0.12πr²+0.06πrh
Recall: ![h=\frac{400}{\pi r^2}](https://tex.z-dn.net/?f=h%3D%5Cfrac%7B400%7D%7B%5Cpi%20r%5E2%7D)
Therefore:
![C(r)=0.12\pi r^2+0.06 \pi r(\frac{400}{\pi r^2})](https://tex.z-dn.net/?f=C%28r%29%3D0.12%5Cpi%20r%5E2%2B0.06%20%5Cpi%20r%28%5Cfrac%7B400%7D%7B%5Cpi%20r%5E2%7D%29)
![C(r)=0.12\pi r^2+\frac{24}{r}](https://tex.z-dn.net/?f=C%28r%29%3D0.12%5Cpi%20r%5E2%2B%5Cfrac%7B24%7D%7Br%7D)
![C(r)=\frac{0.12\pi r^3+24}{r}](https://tex.z-dn.net/?f=C%28r%29%3D%5Cfrac%7B0.12%5Cpi%20r%5E3%2B24%7D%7Br%7D)
The minimum cost occurs when the derivative of the Cost =0.
![C^{'}(r)=\frac{6\pi r^3-600}{25r^2}](https://tex.z-dn.net/?f=C%5E%7B%27%7D%28r%29%3D%5Cfrac%7B6%5Cpi%20r%5E3-600%7D%7B25r%5E2%7D)
![6\pi r^3-600=0](https://tex.z-dn.net/?f=6%5Cpi%20r%5E3-600%3D0)
![6\pi r^3=600](https://tex.z-dn.net/?f=6%5Cpi%20r%5E3%3D600)
![\pi r^3=100](https://tex.z-dn.net/?f=%5Cpi%20r%5E3%3D100)
![r^3=\frac{100}{\pi}](https://tex.z-dn.net/?f=r%5E3%3D%5Cfrac%7B100%7D%7B%5Cpi%7D)
![r^3=31.83](https://tex.z-dn.net/?f=r%5E3%3D31.83)
r=3.17 cm
Recall that:
![h=\frac{400}{\pi r^2}](https://tex.z-dn.net/?f=h%3D%5Cfrac%7B400%7D%7B%5Cpi%20r%5E2%7D)
![h=\frac{400}{\pi *3.17^2}](https://tex.z-dn.net/?f=h%3D%5Cfrac%7B400%7D%7B%5Cpi%20%2A3.17%5E2%7D)
h=12.67cm
The dimensions of the can that will minimize the cost are a Radius of 3.17cm and a Height of 12.67cm.
Answer:
Mean: 7.8
Median: 7
Step-by-step explanation: