SOLUTION: The total surface area of a sphere is given by A= 4πr^2. Find r when the A = 616 cm^2 and π = 22/7?
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Question 898316: The total surface area of a sphere is given by A= 4πr^2. Find r when the A = 616 cm^2 and π = 22/7? Answer by DrBeeee(684) (Show Source):
You can put this solution on YOUR website! GIVEN;
(1) A = 4*pi*r^2
(2) A = 616 cm^2
(3) pi = 22/7
Place A and pi into (1) and get
(4) 616 = 4*(22/7)*r^2
Solve (4) for r^2 and get
(5) r^2 = 616*7/(4*22) or
(6) r^2 = 7*7 or
(7) r = 7
Use (1) to check the value of r.
Is (616 = 4*(22/7)*7^2)?
Is (616 = (88/7)*7*7)?
Is (616 = 88*7)?
Is 616 = 616)? Yes
Answer; r = 7cm.
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