Answer:
The weight of the three blades together is [tex]134\ g[/tex]
Step-by-step explanation:
step 1
Find the area of the circle
The area of the circle is equal to
[tex]A=\pi r^{2}[/tex]
we have
[tex]r=4\ in[/tex]
assume
[tex]\pi=3.14[/tex]
substitute
[tex]A=(3.14)(4)^{2}[/tex]
[tex]A=50.24\ in^{2}[/tex]
step 2
Find the area of the 3 blades
we know that
The area of the 3 blades represent a central angle of 60 degrees, so
its a 1/6 of the area of complete circle
[tex]A=50.24/6=8.37\ in^{2}[/tex]
step 3
Find the weight of the three blades together to the nearest gram
[tex](8.37\ in^{2})*(16\ g/in^{2})=134\ g[/tex]