Hint*** REMEMBER THAT ALL MEASUREMENTS MUST BE IN THE SAME UNITS AND BE CAREFUL THAT YOU DISTINGUISH BETWEEN DIAMETER AND AREA WHEN USING THE FORMULA.......PLEASE HELP IM IN MATH HELL...SO CONFUSED!!!!!
A. 25.12 cu.ft.
B. 50.24 cu.ft.
C. 90.4 cu.ft.
D. 96 cu.ft.
2007-08-28 10:59:40 · 5 answers · asked by jennyjenn518 1 in Science & Mathematics ➔ Mathematics
The answer is A 25.12cu.ft
Working with units is everything, in these types of math problems. So lets get some things straight first.
Area is two dimentional, like length multiplied by width.
The lenght of an object has units of inches, feet, or meters etc.
Example: A sheet of paper 8 1/2 by 11 inches, is
8.5 inches x 11 inches which is equal to 93.5 inches X inches, or (square inches).
Review for lengths in inches:
Units of length is just inches, but the units of Area are (inches times inches) or "square inches".
Volume:
Volume is length times width times hight. So if you use units of inches to measure the volume of a box, that is inches x inches x inches or cubic inches.
If you have a sheet of paper that is 12 inches by 12 inches, that would have an Area of 12 in X 12 in = 144 square inches. If you wanted the volume of a 12x12x12 inch square box, that is 12 in x12 in x12 in or 1728 cubic inches.
Back to your Problem:
Your problem is to find the Volume of a section of pipe. So you will multiply length times width times height, except the pipe is round, not square.
You can first find the Area of a paper thin cross section of the pipe, then multiply by the length to find the volume.
The area of a circle is:
Area=Pie * r * r
where r is the radius, and Pie is a constant = ~ 3.1415926535897932.... and keeps going.
We will approximate the value of pie for this problem to 3.14
In a circle, the radius is half of the diameter.
Because the answers to this problem are in cubic feet for the volume, we will use feet to solve the problem. The length is given in feet, so that is ok. But the diameter is in inches, so we must convert to feet.
There are 12 inches per 1 foot. So 24in x 1ft/12in= 2ft.
The radius is half the diameter, so the radius is 1ft.
The units of inches appears on the top and bottom of the equation above, so the units of inches cancel each other out, leaving units of ft on the top.
The area of the circle of pipe is: Area = Pie * r * r
Area = 3.14 * 1ft * 1 ft = 3.1415 ft*ft or square feet.
To get the volume of the section of pipe, just multiply the area of the circular section by the length of the pipe which is 8ft.
So Volume = 3.14 * 1ft * 1 ft * 8 ft = 25.12 ft * ft * ft or cubic feet.
May the force be with you.....
2007-08-28 11:12:02 · answer #1 · answered by Austin Semiconductor 5 · 0⤊ 0⤋
The volume= 3.14(r^2)(Height) remember the final answer has to be in cubic feet. So you have to convert 24 inch into 2 feet. Radius is one feet. so the answer is
3.14(1^2)(8)= 25.12
2007-08-28 18:12:33 · answer #2 · answered by Anonymous · 0⤊ 0⤋
The volume of a cylinder is pi * r^2*h
the volume of the pipe is, therefore pi *1*8cu ft or 8pi cu ft
That's 25.13cu ft so none of the answers given is correct.
2007-08-28 18:13:23 · answer #3 · answered by tentofield 7 · 0⤊ 0⤋
A = pi(radius)(height)= (pi)(1)(8) =25.12 cu ft
2007-08-28 18:15:21 · answer #4 · answered by xandyone 5 · 0⤊ 0⤋
b
multiply 3.14159265(pi) times the radius and then by the height
2007-08-28 18:16:22 · answer #5 · answered by Melissa R 2 · 0⤊ 0⤋