Author of this question: Kristian Thorsen, Institutt for Data- og Elektroteknologi, Universitetet i Stavanger, Norway
The Tannenbaum family is holding its annual workshop for making Christmas decorations. This year, the goal is creating paper chain garlands and woven paper hearts from pieces of red and green paper sheets. Making garlands requires cutting sheets of paper into four long rectangular strips. Making woven hearts requires shaping sheets of paper as a rectangle with a half-circle added to one of its shorter sides.
Noel Tannenbaum, the youngest child, makes woven hearts in red and green. Each heart requires two pieces: one red and one green rectangle with a half-circle shape.
Yule Tannenbaum, the middle child, makes garlands consisting of red rectangular strips.
Carol Tannenbaum, the oldest child, makes garlands consisting of rectangular strips, alternating red and green colours.
Yule works twice as fast as Noel and Carol, meaning he uses twice the amount of paper as each of the other two over the same period of time.
Mother and Father Tannenbaum sit next to each other, cutting paper sheets. Mother cuts red paper sheets, while Father cuts green ones. Each of them cuts a sheet of paper always in the very same way, making four stripes, one rectangle and one half circle.
They can cut pieces much faster than the children can assemble decorations. However, to avoid unnecessary paper waste, each parent cuts paper only when the child sitting next to them cannot continue the decoration production because pieces of paper of the colour they are cutting are missing. Then, all the cut pieces are handed to the child next to them, regardless of which pieces the child actually needs. The receiving child shares whatever pieces that are not needed at the moment with the other siblings.
Who should sit beside Father and who beside Mother to maximize the Tannenbaum family’s Christmas decoration production?
a. 👶👩🧔👧 Noel should sit next to Mother and Carol next to Father
b. 👦👩🧔👶 Yule should sit next to Mother and Noel next to Father
c. 👧👩🧔👶 Carol should sit next to Mother and Noel next to Father
d. 👦👩🧔👧 Yule should sit next to Mother and Carol next to Father