The left and right side of the brain

If you are right brain dominant, then you are left handed. You are born with this. You cannot change it. 89% of the world's population are right handed.

The brain is cross-wired, meaning that the right side controls the left side of the body and vice versa.
Scientists at the University of Oxford say that the brains of left-handed people work differently than right-handed people.
In a study, the brain was monitored in left-handed participants. Scientists say the two sides of the brain were better connected in lefties and more co-ordinated, particularly in the areas that involve using language.

Prevalence of left-handedness by gender

Males are more likely to be left-handed: than females. 

A meta-analysis of 144 studies indicated that males are about 23% more likely to be left-handed than females. 

For every 4 left-handed women, there are roughly 5 left-handed men.