Question

In an examination, the average of 40 students is
72. afterwards it is found that the marks of three
students are misread as 68, 65 and 73 instead of 64,62
and 84 respectively. Find the correct average?

Answer 1

$40 \times 72 = 2880 - 206 = 2674 + 210 = 2884 \div 40 = 72.1$