Good morning. I am looking at the Pearson Correlation and its not working. can you advise if there is a formula for this problem and how do you come up with the answer? Thank You and have a Great day!

Students participated in a study of the relationship between confidence and college success, with the results, = .78, indicating that 61% of the variance in college success was accounted for by the students' confidence. Upon learning this, your statistics classmate decided that if he worked to increase his confidence, he would certainly become more successful in college. What would you say to him in response to his idea