Correct option is A
1. Students aged 8 years: 20% of the students are 8 years old.
2. Remaining students: 100% - 20% = 80% of the students remain.
3. Students aged 10 years: 50% of the remaining students are 10 years old. So, 50% of 80% = 0.50 x 80% = 40% of the total students are 10 years old.
4. Students aged 15 years: The remaining students are 15 years old. The percentage of these students is: 100% - 20% - 40% = 40%.
5. Calculate the average age of the students:
· Let the total number of students be 100.
· Number of 8-year-old students = 20
· Number of 10-year-old students = 40
· Number of 15-year-old students = 40
· Total age of students = (20 x 8) + (40 x 10) + (40 x 15) = 160 + 400 + 600 = 1160
· Average age of students = 1160 / 100 = 11.6 years.
6. Calculate the percentage of the average age of students to the average age of teachers:
· Average age of teachers = 25 years.
· Percentage = (Average age of students / Average age of teachers) x 100
· Percentage = (11.6 / 25) x 100 = 0.464 x 100 = 46.4%
Therefore, the percentage of the average age of the students to the average age of the teachers is 46.40%.