## hugsandkisses 3 years ago Find the length of the radius of a sphere with a surface area of 78.54 km2. A. 5 ft B. 15 ft C. 10 ft D. 2.5 ft

1. TuringTest

what google didn't work this time?

2. JamesJ

$Surface \ Area = 4 \pi r^2$ where r is the radius. Use this formula to find the answer.

3. FoolForMath

4. TuringTest

$A=4\pi r^2$so$r=\sqrt{\frac{A}{4\pi}}$so plug in the value you are given for the area A, out will come r, your answer, as James will testify

5. hugsandkisses

k, thanks

6. TuringTest

what did you get?

7. FoolForMath

well calculating things is actually hard; no ?

8. TuringTest

It would seem

9. hugsandkisses

wait, what the heck is the radius?

10. rainbow22

11. FoolForMath

yeah it's a heck! what the heck is that!!!

12. GT

That is what needs to be figured out. So, call it r for now.

13. EarthCitizen

Just explain the damn thing!

14. hugsandkisses

oh wait, sorry. that was a dumb question. I was looking at it backwards

15. rainbow22

16. TuringTest

your mantra:$A=4\pi r^2$so$r=\sqrt{\frac{A}{4\pi}}$

17. GT

EarthCitizen - Lot of people dedicate their time to help here. I don't think making demands on them and throwing arrogant insults is the best way to show respect and gratitude for their contributions.

18. FoolForMath

lol Mantra.

19. EarthCitizen

whose arrongant and pompous by teasing ppl for the unfamiliarity with a topic! Focus!

20. TuringTest

where is saifoo? he is neglecting his modship

21. GT

I don't remember anyone making fun of people for not knowing. Nobody even makes fun of not getting it. Yes, sometimes people do expect "learning" and insist on it.

22. hugsandkisses

wait, you guys.. im totally lost :-/ i need help.

23. FoolForMath

pro-tempo-re mods can't be assigned much of tasks

24. TuringTest

Just for good measure$A=4\pi r^2$so$r=\sqrt{\frac{A}{4\pi}}$plug in the surface area (given in the problem) where the A in the formula goes. Out comes r, the answer.

25. EarthCitizen

then tech the best way YOU CAN!

26. FoolForMath

On the contrary I find EarthCitizen a bit swanky.

27. EarthCitizen

teach

28. FoolForMath

TuringTest: May be she needs helps in finding the square root too ?

29. GT

Surface are of sphere = 4*pi*r^2 = 78.54km^2 So, r^2 = 78.54/(4*pi) So, r = SQRT(78.54/(4*pi)) So, r = ?

30. hugsandkisses

2.5?

31. TuringTest

Yes Yes Yes

32. EarthCitizen

yep

33. GT

Yay! Good job.

34. FoolForMath

Congratz.

35. hugsandkisses

oh thank god!

36. FoolForMath

Magnum opus!

37. hugsandkisses

sorry you guys for being so cranky. along with math, I am also completing an essay. lots of work and multi tasking

38. FoolForMath

Apology accepted.

39. GT

We are thick skinned! Glad to see you do it.

40. bimbim2697

GT CAN U HELP ME PLZ?

41. hugsandkisses

thankyou. still a lot more!! have the patience?

42. GT

Well, I am also dark skinned on top!! hahahahaahaha.

43. FoolForMath

lol! I ain't dark skinned like you GT :P

44. EarthCitizen

i see the light in U!

45. Atchyut

First of all question is somewhat wrong!!!!! Radius is a quantity representing length and radius doesn't need to be written as length of the radius. And coming to answer Surface area of sphere is 4*pi*r*r. From that r can be found out substituting others.