How is the percent of contributor increased??

Answer 1

Coder: 50 codes with 5 likes each
Challenger: Win 1000 challenges
Contributor: Answer 50 questions with your answer having 5 likes each
Influencer: 1000 followers
Learner: Learn all SoloLearn course languages fully

Answer 2

by the answers u post for questions and upvotes on them

//like i posted an answer to ur question

Answer 3

Contribute to sololearn by Creating New Quizes. You'll get your answer.