Answer :
The total number of student present in the class is 15.
How to express the number of student in the class?
One-third of the students choose to work on an essay.
Let
x = the total number of student in the class
Therefore,
student that takes essay = 1 / 3 x
One-half of the remaining students choose to read.
Therefore, the expression is as follows
student that choose to read = 1 / 2(x - 1 / 3 x) = 1 / 2( 3x - x/ 3) = 1 / 2(2 / 3 x) = 2 / 6 x = 1 / 3x
The remaining 5 students work on vocabulary. Therefore, the expression is as follows:
Student that works on vocabulary = x - 1 / 3 x - 1 / 3 x
5 = x - 1 / 3 x - 1 / 3 x
5 = 3x- x - x / 3
5 = x / 3
x = 15
Therefore,
the student present in the class = 1 / 3 (15) + 1 / 3(15) + 5
the student present in the class = 5 + 5 + 5
the student present in the class = 15
learn more on expression here: https://brainly.com/question/23747412
#SPJ1