The general formula for the lateral surface area of a regular pyramid is:
Where:
p=perimeter of a base
l=slant height
a.
a=3ft
l=4ft
p=5*a=5*3=15ft
b.
a=2.5ft
l=4ft
p=6*a=6*2.5=15ft
c.
a=1.9ft
l=4ft
p=8*a=8*1.9=15.2ft
d.
Based on a lateral surface area the blue umbrella is best choice. But, the best umbrella overall is the one with the greatest base area. General formula for regular polygon is:
For pentagon:
A=15.48ft^2
For hexagon:
A=16.24ft^2
For octagon:
A=17.43ft^2
Blue umbrella is still best choice.
Where:
p=perimeter of a base
l=slant height
a.
a=3ft
l=4ft
p=5*a=5*3=15ft
b.
a=2.5ft
l=4ft
p=6*a=6*2.5=15ft
c.
a=1.9ft
l=4ft
p=8*a=8*1.9=15.2ft
d.
Based on a lateral surface area the blue umbrella is best choice. But, the best umbrella overall is the one with the greatest base area. General formula for regular polygon is:
For pentagon:
A=15.48ft^2
For hexagon:
A=16.24ft^2
For octagon:
A=17.43ft^2
Blue umbrella is still best choice.