Answer:
Part A:
The surface area of a cylinder is given by
A= 6πr² if h= 2r
Part B:
Total Cost of covering the cylinder = Rate *2πrh + rate*2πr²
Cost of covering only the side = Rate *2πrh
Step-by-step explanation:
Part A:
The surface area of a cylinder is given by
A= 2πrh + 2πr²
Where h= height and radius = r
But we have the height twice as radius so h= 2r
So putting h= 2r we get
A= 2πr(2r) + 2πr²
A= 4πr² + 2πr²= 2πr²(2+1) = 2πr²(3)= 6πr²
Part B:
Cost = Rate * area of the wall + rate * area of the top and bottom
Cost = Rate *2πrh + rate*2πr²
Where area of the top and bottom= πr² +πr² =2 πr²
and area of the side = 2πrh
Multiplying both with the rate and then adding would give the total cost of materials needed to cover the outside of the cylinder and from top and bottom as well.
If you do not need to cover top and bottom then the expression would be
Cost of covering only the side = Rate *2πrh
Part C:
Already done above.
Based on the information given, it can be noted that Tom will use 117 days to read the book.
How to solve a equation.
Based on the information given, we are informed that Tom starts to read a book with 490 pages today. Sundays he reads 25 pages and on all other days he reads 4 pages.
Let the number of days be represented by x. Therefore, the equation to solve the question will be:
25 + (4 × x) = 490
25 + 4x = 490
4x = 490 - 25
4x = 465
x = 465/4
x = 116.25
x = 117
Therefore, he'll use 117 days to read the book.
Learn more about equations on:
brainly.com/question/13763238
It’s 6=6 I think I hope it’s help have a nice day
Answer: 150 boys
Step-by-step explanation:
Let the number of boys be x
Since there were 200 more girls than boys, the number of girls will be: = x + 200
Since the ratio of boys to girls was 3:7, this can be solved further below:
3/7 = x/x+200
Cross multiply
(7 × x) = 3(x + 200)
7x = 3x + 600
7x - 3x = 600
4x = 600
x = 600/4
x = 150
The number of boys enrolled is 150
Number of Girls will be:
= X + 200
= 150 + 200
= 350
Check: Number of boys / Number of girls
= 150/350
= 3/7
= 3:7
Answer:
![= \left[\begin{array}{ccc}1344\\84\\28\end{array}\right] \left \begin{array}{ccc}{0 \ \leq age \leq 1 }\\{ 1 \ \leq age \leq 2 }\\{2 \ \leq age \leq 3}\end{array}\right](https://tex.z-dn.net/?f=%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1344%5C%5C84%5C%5C28%5Cend%7Barray%7D%5Cright%5D%20%20%5Cleft%20%5Cbegin%7Barray%7D%7Bccc%7D%7B0%20%5C%20%20%5Cleq%20%20age%20%20%20%5Cleq%20%201%20%7D%5C%5C%7B%201%20%5C%20%20%5Cleq%20%20age%20%20%20%5Cleq%20%202%20%7D%5C%5C%7B2%20%5C%20%20%5Cleq%20%20age%20%20%5Cleq%203%7D%5Cend%7Barray%7D%5Cright)
i.e after the first year ;
there 1344 members in the first age class
84 members for the second age class; and
28 members for the third age class
Step-by-step explanation:
We can deduce that the age distribution vector x represents the number of population members for each age class; Given that in each class of age there are 112 members present.
The current age distribution vector is as follows:
![x = \left[\begin{array}{ccc}1&1&2\\1&1&2\\1&1&2\end{array}\right] \left[\begin{array}{ccc}{0 \ \leq age \leq 1 }\\{ 0 \ \leq age \leq 2 }\\{0 \ \leq age \leq 3}\end{array}\right]](https://tex.z-dn.net/?f=x%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%261%262%5C%5C1%261%262%5C%5C1%261%262%5Cend%7Barray%7D%5Cright%5D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D%7B0%20%5C%20%20%5Cleq%20%20age%20%20%20%5Cleq%20%201%20%7D%5C%5C%7B%200%20%5C%20%20%5Cleq%20%20age%20%20%20%5Cleq%20%202%20%7D%5C%5C%7B0%20%5C%20%20%5Cleq%20%20age%20%20%20%5Cleq%203%7D%5Cend%7Barray%7D%5Cright%5D)
Also , the age transition matrix is as follows:
![L = \left[\begin{array}{ccc}3&6&3\\0.75&0&0 \\0&0.25&0\end{array}\right]](https://tex.z-dn.net/?f=L%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D3%266%263%5C%5C0.75%260%260%20%5C%5C0%260.25%260%5Cend%7Barray%7D%5Cright%5D)
After 1 year ; the age distribution vector will be :
![x_2 =Lx_1 = \left[\begin{array}{ccc}3&6&3\\0.75&0&0 \\0&0.25&0\end{array}\right] \left[\begin{array}{ccc}1&1&2\\1&1&2\\1&1&2\end{array}\right]](https://tex.z-dn.net/?f=x_2%20%3DLx_1%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D3%266%263%5C%5C0.75%260%260%20%5C%5C0%260.25%260%5Cend%7Barray%7D%5Cright%5D%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%261%262%5C%5C1%261%262%5C%5C1%261%262%5Cend%7Barray%7D%5Cright%5D)
![= \left[\begin{array}{ccc}1344\\84\\28\end{array}\right] \left \begin{array}{ccc}{0 \ \leq age \leq 1 }\\{ 1 \ \leq age \leq 2 }\\{2 \ \leq age \leq 3}\end{array}\right](https://tex.z-dn.net/?f=%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1344%5C%5C84%5C%5C28%5Cend%7Barray%7D%5Cright%5D%20%20%5Cleft%20%5Cbegin%7Barray%7D%7Bccc%7D%7B0%20%5C%20%20%5Cleq%20%20age%20%20%20%5Cleq%201%20%7D%5C%5C%7B%201%20%5C%20%20%5Cleq%20%20age%20%20%20%5Cleq%20%202%20%7D%5C%5C%7B2%20%5C%20%20%5Cleq%20%20age%20%20%20%5Cleq%20%203%7D%5Cend%7Barray%7D%5Cright)
