Height is a trait that shows incomplete dominance. When someone has both the tall and short allele that makes them average height (Tt). If you were to cross an average male with an average female, what would be phenotype percentage of their offspring be?
The offspring receives 50% of its dna from each parent. So mathematically it would have a 50% chance of being average, a 25% chance of being tall, and a 25% chance of being short.