Jack was hired by a farmer to paint the silo on his farm. He only had to paint the curved surface (the cylindrical tube).

Each gallon of paint he was using would cover 300 square feet.

If the silo had a diameter of 28 feet and was 42 feet high, how many gallons of paint would Jack need to complete the job?

13 gallons
31 gallons
15 gallons
11 gallons

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Question

Jack was hired by a farmer to paint the silo on his farm. He only had to paint the curved surface (the cylindrical tube). 

 
Each gallon of paint he was using would cover 300 square feet.

 
If the silo had a diameter of 28 feet and was 42 feet high, how many gallons of paint would Jack need to complete the job?

   13 gallons 
   31 gallons 
   15 gallons 
   11 gallons 

Feedback.

anonymous · Answer

Well the area  formuala is A=2πrh+2πr2 which gives you  4926. And you divide this by 300. This tells you that you need 16 gallons for the whole cylander, So how many do you think you would need for only the curved section?