Following these scenarios are five circuit diagrams from the Crack the Circuit website. If you would like to recreate them and experiment with their operation, you are welcome to do so.

After you read the scenarios, match their names with the diagram that fits their “friendship logic”.

• Dawn realizes that all of her friends like to hang out. In fact, she would not want to be friends with someone who didn’t enjoy hanging out together. Some of her friends like to dance, some of her friends like to knit, and some of her friends like to hike, but she can’t think of any friend that doesn’t do one of these three things.

• Dahlia has many kinds of friends, but she realizes that there are some common factors. Since she loves music, all of her friends either play an instrument, or like to go to concerts. Since she also loves sports, all of her friends either participate in afterschool sports, or like to go to competitions as a fan.

• Destiny realizes that she has two kinds of friends. Some of them live in her neighborhood, and she has been friends with them forever, and has taken a vow to always be their friend, no matter what. For people that she met more recently, she is more picky. If they are not her “neighborhood friends” they have to be funny, nice, and loyal.

• Diego also has two types of friends. One kind of friend is funny and outgoing, and the other kind of friend is always honest and a hard-working student. Since he studies with his hard-working friends, he doesn’t really want them to be funny and outgoing, and when he is just goofing around with his other friends, he doesn’t really want them to be too serious.

• DeAndre has two types of friends, but they all have two things in common. Every one of them laughs at his jokes and he laughs at theirs. Some of them are in chorus with him, and some of them are on his swim team, and a few are in both.

		Whose Friendship Logic Fits This Circuit (and how did you know?)		A and (B or C or D)
		Whose Friendship Logic Fits This Circuit (and how did you know?)		(A and B) or (C and D)
		Whose Friendship Logic Fits This Circuit (and how did you know?)		A and B and (C or D)
		Whose Friendship Logic Fits This Circuit (and how did you know?)		A or (B and C and D)
		Whose Friendship Logic Fits This Circuit (and how did you know?)		(A or B) and (C or D)