The average marks of 50 students in an examination was 65. It was later found that the marks of one student had been wrongly entered as 83 instead of 38. The correct average is?
A batsman scores 98 runs in the 17th match of his career. His average runs per match increased by 2.5. What is his average before the 17th match?
A batsman scores 87 runs in the 21st match of his career. His average runs per match increases by 2. What was his average before the 21st match.