Answer:
The cumulative percentage of fathers who completed only elementary school is nearle 33%.
Explanation:
Among 30 fathers:
- 10 completed only elementary school;
- 10 completed elementary school and high school;
- 7 completed elementary school, high school and college;
- 3 completed elementary school, high school, college and graduate school.
You can fill these numbers into the table:
![\begin{array}{cccc}&\text{Frequency}&\text{Cumulative frequency}&\text{Cumulative percentage}\\\text{Elementary school}&10&10&\approx 33\%\\\text{El. and high school}&10&20&\approx 67\%\\\text{El., high schools and college}&7&27&90\%\\\text{El., high, college and grad. sch.}&3&30&100\%\end{array}]()
The cumulative percentage of fathers who completed only elementary school is nearle 33%.