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The base of an auditorium is in the form of an ellipse 200 ft. long and 100 ft. wide. A pin dropped near one focus can clearly be heard at the other focus. Determine the distance between the foci to the nearest tenth of a foot

User Chandmk
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2 Answers

3 votes

Answer:

173.21 ft

Explanation:

User Page
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6 votes
The ellipse has major axis of 200 ft and minor axis of 100 ft
The semi major axis, a = 100 ft
The semi minor axis, b = 50 ft
The distance from the center to the focus, c, is calculated using
a² = b² + c²
Substituting and solving for c
c = 86.60 ft
The distance between the two focci is twice the value of c
2(86.60) = 173.21 ft
User Toma Nistor
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