5 students offers all the two subjects.
Student that offers Physic only = 15 students
Student that offers chemistry only = 13 students
Students that offers only one subject = 28 students
Total student in the class = 35
20 offer physics.
18 offer chemistry
2 offer neither physics nor chemistry.
Therefore,
x = student that offer both subject
35 = 20 + 18 - x + 2
35 - 2 - 20 - 18 = -x
-5 = -x
x = 5
Therefore, 5 students offers all the two subjects.
Student that offers Physic only = 20 - 5 = 15
Student that offers chemistry only = 18 - 5 = 13
Students that offers only one subject = 13 + 15 = 28
learn more on Venn diagram here: https://brainly.com/question/27808502
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