What is the average of marks obtained by all the students in subject B?

Options

A. 71.4
B. 73.14
C. 107.14
D. 114.07

Answer

To find the average of marks obtained by all the students in subject B, we will follow these steps:

### Step 1: List the Marks
First, we need to list the marks obtained by each student in subject B. According to the information provided, the marks are:
- P: 68
- Q: 72
- R: 75
- S: 62
- T: 75
- V: 80
- W: 68

### Step 2: Calculate the Total Marks
Next, we will add all the marks together to find the total marks obtained by all students:
\[ \text{Total Marks} = 68 + 72 + 75 + 62 + 75 + 80 + 68 \]
Calculating this step-by-step:
- \(68 + 72 = 140\)
- \(140 + 75 = 215\)
- \(215 + 62 = 277\)
- \(277 + 75 = 352\)
- \(352 + 80 = 432\)
- \(432 + 68 = 500\)

So, the total marks obtained by all students in subject B is **500**.

### Step 3: Count the Number of Students
Now, we need to count the number of students who took the subject B exam. From the list, we see there are 7 students (P, Q, R, S, T, V, W).

### Step 4: Calculate the Average Marks
To find the average marks, we will divide the total marks by the number of students:
\[ \text{Average Marks} = \frac{\text{Total Marks}}{\text{Number of Students}} = \frac{500}{7} \]
Calculating this gives:
\[ \text{Average Marks} \approx 71.43 \]

### Step 5: Round the Average (if necessary)
In this case, we can round the average to one decimal place, which gives us **71.4**.

### Final Answer
The average of marks obtained by all the students in subject B is **71.4**.

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