Madge describes herself (and is described by her friends) as being conforming, predictable, and rather unimaginative. According to the Big Five model of personality, Madge would be high on the personality dimension of?

The answer is extraversion.

Explanation:

Extroverted people usually conform to their social environents and base their activities on external means. In other words, they enjoy interacting with people and tend to be enthusiastic. For this reason, it's possible to assume that extroverts will usually "go with the flow" and their behaviours are preducted by their social context.