GRE北美题No10-5.docVIP

No.9 第五套 Questions 1-6 Two maps are being designed. One will show subway lines; the other will show bus routes. There are three subway lines and four bus routes, and each line or route must be represented on the maps by a color used to represent it only. The colors available to the designer of the maps are blue, green, orange, purple, red, tan, and yellow. Any assignment of colors to lines and routes is acceptable provided the following condi- tions are met: Blue cannot be used on the same map as purple. Orange cannot be used on the same map as red, nor on the same map as yellow. 1. If blue is used on the subway map, which of the following must be true? (A) Orange is used on the subway map. (B) Yellow is used on the subway map. (C) Purple is used on the bus map. (D) Green is used on the bus map. (E) Red is used on the bus map. 2. If red is used on the bus map, which of the following colors must be used on the subway map? (A) Blue (B) Orange (C) Purple (D) Tan (E) Yellow 3. If yellow and purple are used on the subway map, the third color used on that map must be (A) blue (B) green (C) orange (D) red (E) tan 4. If red and blue are used on the bus map, which of the following could be the other two colors used on that map? (A) Green and purple (B) Green and tan (C) Green and yellow (D) Orange and tan (E) Purple and yellow 5. If green is not used on the same map as blue, nor on the same map as yellow, which of the following must be true? (A) Blue is used on the subway map. (B) Blue is used on the bus map. (C) Green is used on the same map as red. (D) Purple is used on the same map as orange. (E) Tan is used on the same map as red. 6. There will be only one acceptable assignment of colors to each of the two maps if which of the following conditions is added to the original ones? (A) Purple and tan must be used on the subway map. (B) Green and purple must be used on the bus map. (C) Bl