A searchlight on top of the watchtower makes 4 revolutions per minute. What is the probability that a man appearing near the tower will stay in the dark for at least 12 seconds?	Pick one.
A) 1/2	B) 2/3	C) 1/3	D) 1/4	E) 1/5
The searchlight completes one revolution every 15 seconds.   The probability that the man's area will be lit up is 12/15=4/5.   The probability that he will stay in the dark is 1-4/5=1/5   The answer is 1/5.
<result>E</result>
A searchlight on top of the watchtower makes 4 revolutions per minute. What is the probability that a man appearing near the tower will stay in the dark for at least 12 seconds?