Answer:[tex]4.71\ in.[/tex]
Step-by-step explanation:
Given
diameter of pie is [tex]d=9\ inch[/tex]
radius [tex]r=\frac{9}{2}=4.5\ inch[/tex]
If child divides pie into 12 equal parts then each part subtends an angle of
[tex]=\frac{360^{\circ}}{12}=30^{\circ}[/tex] at the center
and crust length of single piece is
[tex]=\frac{30}{360}\times 2\pi r[/tex]
[tex]=\frac{1}{12}\times 2\times \pi \times 4.5[/tex]
[tex]=2.35\ in.[/tex]
For two slice length is [tex]2\times 2.35=4.71\ in.[/tex]
Thus the total length of crust eaten is [tex]=4.71\ in.[/tex]