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At a bus stop, a bus arrives every 8 minutes, waits exactly 1 minute, and then leaves.
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minutes for a bus to arrive?
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)LJXUH is a schematic time line.
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1-minute interval with a waiting bus.
The probability of seeing a bus is thus^18.
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we are in the last 2 minutes of that period is^27.
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A dart is thrown at random at the following diagram of a square
inscribed in a circle, which is inscribed in a square. What are the chances
that it lands in any of the shaded regions shown in )LJXUH?
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6XSSRVHWKDWWKHUDGLXVRIWKHFLUFOHLVr. Then, the side length of the
large square is 2 22 r, and the side length of the small square is
rr 2.r The probability we seek is as follows.
Probability
(^2222)
Srr 2 r 222 SSrr 4 r^224.
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x Drawing a picture to accompany a word problem often reveals the steps needed to solve the problem.
Figure 25.3
Figure 25.4