In a class of 100 students, 40 offer Biology and 10 offer Chemistry and Biology .10 offer Physics and Chemistry , and 30 offer Physic and Biology . Each student offer at least one of the three subjects. The number
Complete your question. Also, students don't "offer" courses, they "take" them. The teachers offer the courses.
Please solve okay
To find the number of students who offer all three subjects (Biology, Chemistry, and Physics), we can use the principle of inclusion-exclusion.
First, we observe that a total of 40 students offer Biology, 10 students offer Chemistry and Biology, and 30 students offer Physics and Biology.
To find the number of students who offer Biology or Chemistry or Physics, we add these three numbers together: 40 + 10 + 30 = 80.
However, by doing that, we have counted the students who offer both Biology and Chemistry (10 students) twice. To fix this, we need to subtract the number of students who offer both Biology and Chemistry.
So, we subtract 10 from 80: 80 - 10 = 70.
Now, we have counted the 70 students who offer Biology, Chemistry, or Physics once, but we have also counted the students who offer both Physics and Biology (30 students) twice.
To correct this, we need to subtract the number of students who offer both Physics and Biology.
So, we subtract 30 from 70: 70 - 30 = 40.
Therefore, there are 40 students who offer all three subjects: Biology, Chemistry, and Physics.