In detail

Deciding what clothes to wear

Deciding what clothes to wear

Tired of spending hours in front of the closet to decide what to wear, I have established a simple guideline to select the clothes I will use every day of the week.

I have three red, green and yellow cotton shirts and two linen shirts, one blue and one black. Every day of the week, from Monday to Sunday, I wear two shirts, one in the morning in cotton and one in the afternoon in linen and I decide on the clothes I will wear according to the following criteria:

  1. I don't use the same color scheme two days of the same week.
  2. I don't wear a cotton shirt for two consecutive days.
  3. I wear a cotton shirt four days a week.
  4. I wear linen shirt on Mondays.
  5. On Thursdays I wear the green one.
  6. I don't wear the yellow shirt on Friday.
  7. I do not combine the colors red and black the same day.

What shirts touch me this Saturday?

Solution

From conditions 2 and 3 we deduce that I wear a cotton shirt on Mondays, Wednesdays, Fridays and Sundays. The other shirt will be linen, blue or black.

If I wear the black one, from conditions 1 and 4 it can be deduced that I will combine it with red, yellow or green on Wednesdays, Fridays and Sundays but condition 7 does not allow the combination of black with red. Therefore, I will have to use the blue one and I will have to combine it with the red, yellow or green one on Wednesday, Friday and Sunday.

From condition 5 it follows that I use the green one on Thursday and I cannot use the green one on Wednesday or Friday, only on Sunday.

By condition 6 it follows that I don't wear yellow on Fridays and that I can only use red and yellow on Wednesdays. Since I wear the blue, red and green shirts on Friday and Sunday, from condition 2, I can only wear black and yellow on saturdays.