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15 votes
15 votes
15. PLEASE HELP ME

A sports recreation company plans to manufacture a beach ball with a surface area of 7238 in.2 Find the radius of the beach ball. Use the formula A= 4\pir2, where A is the surface area and r is the radius of the sphere.

A. 48 in.

B. 24 in.

C. 75 in.

D. 576 in.

User David Arango
by
3.3k points

2 Answers

12 votes
12 votes

Answer:

B. 24 in.

Explanation:

The given problem supplies as with the surface area of the beach ball and we are to look for the required radius. Assuming that the beach ball is perfectly shaped in the form of a sphere, then the formula for calculating the surface area of a sphere is given as:

SA = 4 π r^2

where r is the radius of the sphere and SA is the surface area which is given to be 7238 in^2

Rewriting the formula in terms of r:

r^2 = SA / 4 π

r = sqrt (SA / 4 π)

Solving for r:

r = sqrt (7238 in^2 / 4 π)

r = 24 in

Answer:

24 inches

User Douglas Mauch
by
2.9k points
23 votes
23 votes
  • Surface Area=7238in^2

We know


\boxed{\sf Surface\:area=4\pi r^2}


\\ \sf\longmapsto 4\pi r^2=7238


\\ \sf\longmapsto 4* (22)/(7)r^2=7238


\\ \sf\longmapsto r^2=(7238* 7)/(88)


\\ \sf\longmapsto r^2=(5066)/(88)


\\ \sf\longmapsto r^2=575.75


\\ \sf\longmapsto r^2\approx576


\\ \sf\longmapsto r\approx√(576)


\\ \sf\longmapsto r\approx24in

Option b is coreect

User MLEN
by
2.9k points