Concept:The number pair (a,b) is converted by writing (a−b) followed by (a+b) as a single number.Explanation:Check the given examples:(6,3)⇒(6−3)=3 and (6+3)=9, so the result is 39.(5,1)⇒(5−1)=4 and (5+1)=6, so the result is 46.(7,3)⇒(7−3)=4 and (7+3)=10, so the result is 410.(5,3)⇒(5−3)=2 and (5+3)=8, so the result is 28.Now apply the same rule to (6,1).(6−1)=5 and (6+1)=7.Combine them as 57.Answer:57