Answer:
25%
Step-by-step explanation:
Since it's only asking for the percent of 6th graders, we can ignore the second row of numbers.
We start off by adding the total number of students in 6th grade which is 40.
After that we use the number of students invovled in the book club (10) and divide it by the total number of 6th grade students.
This will give us the amount of times we would need to times before reaching the total amount of 6th graders.
Which would be 40 / 10 = 4
Since 40 is the total number of students we can transform it into a percent of 100%
We then divide this percentage by 4
100 / 4 = 25
