A ship captain looks up at the top of a lighthouse at a 7 degree angle of elevation and calculates that he is 1221 feet from its
1 answer:
You might be interested in
Given:
The largest circle has a radius of R=7 units.
Let x be the radius of the large shaded circle.
The small shaded circles have a radius of 1/5 of the large shaded circle.
=> the small shaded circles have a radius of r=x/5
By adding up radii, we have the equation
2(r+x+r)=2(x/5+x+x/5)=2R=2*7=14
Simplify:
7x/5=14/2
x=5
=> r=1
Area of outer circle =
Area of large shaded circle =
Area of 4 small shaded circles =
Total area of shaded circles =
Shaded area as a fraction of that of the outer circle
The largest circle has a radius of R=7 units.
Let x be the radius of the large shaded circle.
The small shaded circles have a radius of 1/5 of the large shaded circle.
=> the small shaded circles have a radius of r=x/5
By adding up radii, we have the equation
2(r+x+r)=2(x/5+x+x/5)=2R=2*7=14
Simplify:
7x/5=14/2
x=5
=> r=1
Area of outer circle =
Area of large shaded circle =
Area of 4 small shaded circles =
Total area of shaded circles =
Shaded area as a fraction of that of the outer circle
