In a class of 200 students passed in mathematics, 60 students failed only in chemistry and 30 students failed in both the subjects. How many students passed exactly in one subject?Choices:- 100 120 135 150

To solve this problem, we need to understand that the students who passed in mathematics may or may not have passed in chemistry.

Step 1: We know that 200 students passed in mathematics.

Step 2: Out of these 200 students, 30 students failed in both subjects. This means that these 30 students passed in mathematics but failed in chemistry.

Step 3: We also know that 60 students failed only in chemistry. This means that these 60 students passed in mathematics and failed in chemistry.

Step 4: To find out how many students passed exactly in one subject, we need to add the number of students who passed in mathematics but failed in chemistry (30 students) to the number of students who passed in mathematics and failed only in chemistry (60 students).

So, 30 students + 60 students = 90 students.

Therefore, 90 students passed exactly in one subject.

However, none of the choices matches this answer. There might be a mistake in the problem or the choices given.

To solve this problem, we need to understand that the students who passed in both subjects are the ones who passed in mathematics but did not fail in chemistry.

Step 1: We know that 200 students passed in mathematics.

Step 2: Out of these 200 students, 30 students failed in both subjects (mathematics and chemistry). So, the number of students who passed in both subjects is 200 - 30 = 170 students.

Step 3: We also know that 60 students failed only in chemistry. These students passed in mathematics but not in chemistry. So, they are also part of the 170 students who passed in both subjects.

Step 4: Therefore, the number of students who passed exactly in one subject is 170 (students who passed in both subjects) - 60 (students who failed only in chemistry) = 110 students.

So, the answer is not in the choices given. There seems to be a mistake in the question or the choices provided.

To solve this problem, we need to understand that the students who passed exactly in one subject are those who passed in mathematics but failed in chemistry, and those who passed in chemistry but failed in mathematics.

From the problem, we know that:

• 200 students passed in mathematics.
• 60 students failed only in chemistry. This means they passed in mathematics.
• 30 students failed in both subjects.

So, the students who passed in mathematics but failed in chemistry are 60 (those who failed only in chemistry).

However, we also know that 30 students failed in both subjects. This means that these 30 students are not included in the 200 students who passed in mathematics. Therefore, the number of students who passed in mathematics and chemistry is 200 - 30 = 170.

Since 60 of these 170 students failed in chemistry, the number of students who passed in both subjects is 170 - 60 = 110.

Therefore, the number of students who passed exactly in one subject is 200 (total students who passed in mathematics) - 110 (students who passed in both subjects) = 90.

So, none of the choices are correct. The number of students who passed exactly in one subject is 90.