Tony is building a new silo to store corn as animal feed. It will be a cylinder topped with a half-sphere, and must store 21 000
t of corn. The entire silo can be filled with corn. Tony wants to minimize the surface area of the silo to reduce materials and paint costs. He has the following information: • 1 cubic m of corn has a mass of 700 kg.
• Building costs are $8/m2, taxes included.
• Paint comes in 3.8 L cans.
Each can covers 40 sq m and costs $35,
taxes included.
• Corn costs $140 per tonne ($140/t), taxes
included.
What is the total cost to build, paint, and fill a silo with the least surface area?
let x and y be the number of chip and pretzel bags respectively :
4x%2B2y%3 C=20
:
if x=1 then 4%281%29%2B2y%3C=20--->{{2y<=16}}}--->y%3C=8 :
if x=3 then 4%283%29%2B2y%3C=20--->{{2y<=8}}}--->y%3C=4 :
so chips 1 and pretzels 8 :
chips 3 and pretzels 4.
