Surface area of half of sphere with r=10 (can't get answer)

[K‡rbyroth]

radius = 10

4*3.14*10^2 = 1256/2 = 628

Iam getting the answer wrong i don't know why.

 

[Denis]

Re: Surface area of half a sphere

Looks good to me: WHO says it's wrong?

 

[K‡rbyroth]

Re: Surface area of half a sphere

the A+ program i using

 

[Denis]

Re: Surface area of half a sphere

Does it use 3.14 for pi, or the real pi of 3.1415926..... ?

 

[fasteddie65]

Re: Surface area of half a sphere

If the surface area of a sphere is 4?r^2, shouldn't the surface area of a hemisphere (half a sphere) be 2?r^2?

 

[Denis]

Re: Surface area of half a sphere

If the surface area of a sphere is 4?r^2, shouldn't the surface area of a hemisphere (half a sphere) be 2?r^2?

He DID divide by 2: 4*3.14*10^2 = 1256/2 = 628