if the diameter of a sphere is 7,900 mi. what is the surface area? and how do you find out the answer?
2006-08-22 11:12:58 · 6 answers · asked by nate_n_s 1 in Education & Reference ➔ Homework Help
u use this formula "4 pi r^2"
since the diameter is 7900, the radius is the half of 7900=3950
then u square the radius= 3950^2= 15602500 or just enter 3950^2 to ur calculator
then u plug them in....
4 x [pi or 3.1416] x 3950^2= approx.--> 196,066,797.5
there!
2006-08-22 11:21:48 · answer #1 · answered by Anonymous · 0⤊ 0⤋
what is the formula for finding surface area?? found it on this site:
http://www.math.com/tables/geometry/surfareas.htm#sphere
Surface Area of a Sphere = 4 pi r 2
sooo.. r= radius, so divide the diameter u get the radius! 7900/2 = 3950
4 x pi x 3950 = 15800pi
2006-08-22 18:20:04 · answer #2 · answered by sasmallworld 6 · 0⤊ 0⤋
Multiply it by the total area of the circle and then divide your answer by 1/4.
2006-08-22 18:20:09 · answer #3 · answered by dinochirus 4 · 0⤊ 0⤋
formula is 4 times pi times radius squared. now you should be able to do the math.
2006-08-22 18:15:59 · answer #4 · answered by Dana 4 · 1⤊ 0⤋
find out yoor self thats called cheating go to a website that helps u on math
2006-08-22 18:15:45 · answer #5 · answered by mehnazq 2 · 0⤊ 2⤋
I don't know can't bother now it's almost 2 am
2006-08-22 18:14:15 · answer #6 · answered by Pearl 5 · 0⤊ 2⤋