Answer:
1.60 ![ft^{2}](https://tex.z-dn.net/?f=ft%5E%7B2%7D)
Step-by-step explanation:
Assuming that this is a cylindrical pipe, the area can be determined by applying the formula for calculating the area of a circle.
i.e Area = ![\pi](https://tex.z-dn.net/?f=%5Cpi)
![r^{2}](https://tex.z-dn.net/?f=r%5E%7B2%7D)
So that,
for the inner part of the pipe,
r = ![\frac{diameter}{2}](https://tex.z-dn.net/?f=%5Cfrac%7Bdiameter%7D%7B2%7D)
= ![\frac{5}{2}](https://tex.z-dn.net/?f=%5Cfrac%7B5%7D%7B2%7D)
= 2.5 feet
Area of the inner part of the pipe = ![\pi](https://tex.z-dn.net/?f=%5Cpi)
![r^{2}](https://tex.z-dn.net/?f=r%5E%7B2%7D)
= 3.14 x ![(2.5)^{2}](https://tex.z-dn.net/?f=%282.5%29%5E%7B2%7D)
= 19.625
Are of the inner part of the pipe is 19.63
.
Total diameter of the pipe = 5 + 0.2
= 5.2 feet
r = ![\frac{5.2}{2}](https://tex.z-dn.net/?f=%5Cfrac%7B5.2%7D%7B2%7D)
= 2.6 feet
Area of the pipe = ![\pi](https://tex.z-dn.net/?f=%5Cpi)
![r^{2}](https://tex.z-dn.net/?f=r%5E%7B2%7D)
= 3.14 x ![(2.6)^{2}](https://tex.z-dn.net/?f=%282.6%29%5E%7B2%7D)
= 21.2264
Area of the pipe is 21.23
.
Thus the cross sectional area = Area of the pipe - Area of the inner part of the pipe
= 21.2264 - 19.625
= 1.6014
The cross sectional area of the cement pipe is 1.60
.
-1 cus its -1 becus u -1 so u get -1
The answer is 900 because 10 boxes multiplied by 9 is 900