At the second roll call, the number of people present is10+1=11times the number of people absent.

The number of absentees is1(11+1) =112.

Add three people, add three people to attend, and reduce three people's absence.

The number of people absent at the first roll call accounts for1/(7+1) =1/8 of the total number of people.

So the total is:

3/( 1/8- 1/ 12) = 72.