## GREATEST COMMON DIVISOR

**Keywords - **Greatest common divisor, prime factors.

**Purpose - **Understanding the mechanics of greatest common divisor.

**Description - **The trainer divides the group into subgroups of 3 or 4 people.

Each subgroup has to stage a vacation with precise characteristics. Every participant in the subgroups expresses 5 desires for the vacation that will be represented. For example: at the sea, relaxing, biking, abroad, reading a lot or biking in a city full of cultural sites, etc. The subgroup must imagine and stage a vacation that only includes the desires expressed in common by all the members of the group. The piece should be rehearsed before it is performed in front of the others.

**Duration - **About 30 minutes.

**Observations - **The process of creating the vacation is a metaphor for the mechanism of
calculating the greatest common divisor: only the common desires (prime
factors) are considered of all the participants (numbers). In this exercise the
exponent is not considered but through the tests carried out with groups it
emerged that the abstraction presented is adequate to understand the heart of
the concept of the greatest common divisor. The exponent can be introduced
subsequently during a frontal lesson.

In order for the activity to function, it is important that the group have the capacity to work together and theatrically depict a situation.