Answer:
There are 405 students at the school altogether
Explanation:
andersonmiguelolivei already put the right answer in the comments, but I'll show you how we can get to that answer using variables.
Creating variables:
- We can allow x to represent the total number of students at the school.
- We can allow y to represent the number of students who have had chickenpox.
- Since 0.6 of the total number of students have had chickenpox, we can represent this with the following equation:
(0.6 * total number of students) = number of students with chickenpox
0.6x = y
Since 162 students have not had chickenpox, we know that:
- the difference of the total number of students and the students who have had chickenpox equals the number of students who have not had chickenpox
Thus, we have the equation:
x - y = 162
Solving for x, the total number of students, with substitution:
Now we can plug 0.6x for y to solve for x, the total number of students at the school:
x - 0.6x = 162
(0.4x = 162) / 0.4
x = 405
Thus, there are 405 students at the school altogether.
Checking the validity of our answer:
We know that the total number of students consists of both the students who have had and the students who have not had chickenpox.
Finding the number of students who have had chickenpox:
Thus, we first need to find the number of students who have had chickenpox by multiplying 0.6 by 405:
0.6 * 405
243
Thus, 243 students have had chickenpox.
Determining whether the sum of the students who have had and who have not had chickenpox equals the total number of students:
Now we must check that the sum of 243 and 162 equals 405, which will prove that we've correctly determined the total number of students at the school:
243 + 162
405
Thus, our answer is correct and there are indeed 405 students at the school altogether.