Questions 7-11
A worker will insert colored light bulbs into a billboard1 equipped with exactly three light sockets2, which are labled lights 1, 2, and 3. The worker has three green bulbs, three purple bulbs, and three yellow bulbs. Seiection of bulbs for the sockets is governed by the following conditions:
Whenever light 1 is purple, light 2 must be yellow.
Whenever light 2 is purple, light 1 must be green.
Whenever light 3 is either purple or yellow, light 2 must be purple.
7. Which one of the following could be an accurate list of the colors of light bulbs selected for lights 1, 2 and 3, respectively?
green, green, yellow
purple, green, green
purple, purple, green
yellow, purple, green
yellow, yellow, yellow
8. If light 1 is yellow, then any of the following can be true, EXCEPT:
Light 2 is green.
Light 2 is purple
Light 3 is green
Light 3 is purple
Light 3 is yellow
9. There is exactly one possible color sequence of the three lights if which one of the following is true?
Light 1 is purple.
Light 2 is purple.
Light 2 is yellow
Light 3 is purple.
Light 3 is yellow
10. If no green bulbs are selected, there are exactly how many possible different color sequences of the three lights?
one
two
three
four
five
11. If no two lights are assigned light bulbs that are the same color as each other, then which one of the following could be true?
Light I is green, and light 2 is purple.
Light I is green, and light 2 is yellow.
Light I is purple, and light 2 is yellow.
Light I is yellow, and light 2 is green.
Light I is yellow, and light 2 is purple
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