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0 sats \ 5 replies \ @Scroogey 14 Dec 2024 \ parent \ on: [Not-so-daily puzzle] Purple area science
I guess the question is, are the green lines intersecting chords through one and the same point?
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deleted by author
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If we look at the upper blue region:
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The area is the sum of the components:
A = g * (t + \frac{s}{2}) + u*s + u*t
Adding the same (with
h
instead of g
) for the lower blue region:38 = (g+h)*(t + \frac{s}{2}) + 2*u*s + 2*u*t
The apothem formula gives
tan(\frac{\pi}{24})*(g+h+2*u) = s
Simple trig says
t = s*cos(15°)
u = s*sin(15°)
Those last four equations solve for
s \approx 1.82625
, or total area of polygon A=152
.As seen in @0xbitcoiner's drawing, the total area is the sum
38 + 47 + 47 + 2 * x = 152
Therefore,
x = 10
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I'm not going to be the one checking those calculations! 😎👍
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Correct, the area of the magenta region equals $10$.
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