Answer:
2/11
Explanation:
Normally 22 kids. 22 kids on the attendance roster.
18 kids say, "Here!" when their name is called.
22 - 18 is 4. 4 kids don't say anything when their name is called because they are at home still. 4 kids absent.
4 out of 22 kids absent. 4/22 kids absent.
4/22 simplifies to 2/11.
2/11 of the kids are absent.