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\includegraphics[alt={},max width=\textwidth]{ba9f2fd1-7a36-4749-86ec-40c93d23a84b-4_709_709_262_303}
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\caption{Fig. 13.1}
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\includegraphics[max width=\textwidth, alt={}]{ba9f2fd1-7a36-4749-86ec-40c93d23a84b-4_392_544_415_1197}
In a concert hall, seats are arranged along arcs of concentric circles, as shown in Fig. 13.1. As shown in Fig. 13.2, the stage is part of a sector ABO of radius 11 m . Fig. 13.2 also gives the dimensions of the stage.
- Show that angle \(\mathrm { COD } = 1.55\) radians, correct to 2 decimal places. Hence find the area of the stage.
- There are four rows of seats, with their backs along arcs, with centre O, of radii \(7.4 \mathrm {~m} , 8.6 \mathrm {~m} , 9.8 \mathrm {~m}\) and 11 m . Each seat takes up 80 cm of the arc.
(A) Calculate how many seats can fit in the front row.
(B) Calculate how many more seats can fit in the back row than the front row.