Brain Teasers
Five Coloured Shirts
Every day from Monday through Sunday in this week, Mr. Peter picks two shirts from the five colours red, blue, yellow, green and black. Peter follows the rules:
1. Peter doesn't use the same combination on two days of this week.
2. Peter doesn't use the same colour on two consecutive days of this week.
3. Peter uses some colour on four days.
4. Peter uses blue and black on Monday.
5. Peter uses green on Thursday.
6. Peter doesn't use yellow on Friday.
7. Peter doesn't combine red with black.
What colours does Peter use on Saturday?
1. Peter doesn't use the same combination on two days of this week.
2. Peter doesn't use the same colour on two consecutive days of this week.
3. Peter uses some colour on four days.
4. Peter uses blue and black on Monday.
5. Peter uses green on Thursday.
6. Peter doesn't use yellow on Friday.
7. Peter doesn't combine red with black.
What colours does Peter use on Saturday?
Answer
From rules 2 and 3, Peter must use one colour on Monday, Wednesday, Friday and Sunday, which can be blue or black.If it's black, from rules 1 and 4, Peter must combine black with red, yellow and green on Wednesday, Friday and Sunday, but rule 7 disallows combining black with red.
Therefore, it's blue, and Peter must combine blue with red, yellow and green on Wednesday, Friday and Sunday. From rule 5, Peter uses green on Thursday, he can't use green on Wednesday or Friday, and only on Sunday.
From rule 6, Peter doesn't use yellow on Friday, and he can only use red on Friday and yellow on Wednesday.
Since Peter uses blue, red and green on Friday and Sunday, from rule 2, he can only use black and yellow on Saturday.
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Comments
wow! thats a toughy! good one though!
Mr. Peter is a veeeeeeery funny man.... (:
great teaser, got my brain working. My only concern is for Mr. Peter and his need to wear 2 shirts everyday...
Great teaser!
Took me a while to realize I was going to have to have either black or blue on Wed, Fri and Sun in order to avoid having the 4-day color next to a day of same color. I recognized one color would be 4 days, 2 colors would be 3 days and 2 colors would be 2 days and still had a hard time realizing that. Once I got over that hump, it was all downhill. Thanks for a fun morning!
Took me a while to realize I was going to have to have either black or blue on Wed, Fri and Sun in order to avoid having the 4-day color next to a day of same color. I recognized one color would be 4 days, 2 colors would be 3 days and 2 colors would be 2 days and still had a hard time realizing that. Once I got over that hump, it was all downhill. Thanks for a fun morning!
HAHA!! Peter NEEDS to get over his weird habits! But thanks for sharing!!!
The correct answer is yes
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