10 is a good number because is what adds to 100 and the number 100 is lucky. This is what i think.
The answer is: The first triangle. The reasons are shown below:
1. All the triangles are rigth triangles, because they have an angle of 90°. So, let's calculate the others angles of the first one:
Tan(α)^-1= opposite leg/adjacent leg
Opposite leg=5
Adjacent leg=5√3
Tan(α)^-1= 5/5√3
Tan(α)^-1=30°
2. Let's calculate the other angle:
Tan(α)^-1= opposite leg/adjacent leg
Now, the opposite leg will be 5√3 and the adjacent leg will be 5. Then:
Tan(α)^-1= 5√3/5
Tan(α)^-1=60°
As you can see, the angles of first triangle are: 30°,60° and 90°.
We know that
[the area of a circle]=pi*r²
for r=4 ft
[the area of a circle]=pi*4²------> 50.24 ft²
if 2π radians ( full circle) has an area of-----------------> 50.24 ft²
5π/2 radians--------------------------------------> X ft ²
X=(5π/2)*50.24/2π-------> 62.8 ft²
the answer is
62.8 ft²
For the diagonal of the floor:
20^2 + 48^2= c^2
400+2304= c^2
c=52
For the diagonal of the cube:
52^2 + 10^2 = c^2
2704+100=c^2
c=52.95
Rounded= 53
Tell me if this helps!!!