Posted by Mike on .
Using the formula for the surface area of a SPHERE:
Use Pi = 3.14
If the diameter of a sphere is 8 feet, find the surface area (round to the nearest square foot)
201 sq ft
If a quart of paint covers 75 square feet, how many quarts of paint are needed to paint the surface? quarts
What is the volume of the sphere? (round to the nearest cubic foot)
268 cubic ft
Using the rounded answer from the previous question, how many gallons of water can be stored in the sphere if 1 gallon= 231 cubic inches? (round this answer to the nearest TENTH of a gallon!)
are the two correct that i have done and how do i find the other two
radius of sphere = 4 feet
surface area of sphere = 4pir^2
= 4pi(16) = 200.96 feet^2 or 201 feet^2
so your first part is correct.
201/75 = 2.67 quarts
so you will have to buy 3 quarts
your volume answer is correct.
I trust that your statement
1 gallon = 231 cubic inches is correct, since I don't use those old units.
1 cubic foot = 12^3 cu inches = 1728 cubic inches.
so the 268 cubic feet from your answer equal 268*1728 or 463104 cubic inches.
463104/231 = 2005
there would be 2005 gallons of water