Arun scored 36 marks in English , 44 marks in Hindi, 75 marks in mathemations and x marks in science . If the has secured an average of 50 marks, five the value of x.

Answer

To find the value of x, we will use the formula for the average. The average is calculated as the sum of all observations divided by the total number of observations.

### Step-by-Step Solution:

1. **Identify the Scores**:
- Arun's scores are:
- English: 36 marks
- Hindi: 44 marks
- Mathematics: 75 marks
- Science: x marks

2. **Set Up the Average Formula**:
- The average score is given as 50 marks.
- The formula for average is:
\[ \text{Average} = \frac{\text{Sum of all scores}}{\text{Number of subjects}} \]
- In this case, the number of subjects is 4.

3. **Write the Equation**:
- Plugging in the known values into the average formula, we get:
\[ 50 = \frac{36 + 44 + 75 + x}{4} \]

4. **Multiply Both Sides by 4**:
- To eliminate the denominator, multiply both sides of the equation by 4:
\[ 200 = 36 + 44 + 75 + x \]

5. **Calculate the Sum of Known Scores**:
- Now, calculate the sum of the scores:
\[ 36 + 44 + 75 = 155 \]
- So, the equation now becomes:
\[ 200 = 155 + x \]

6. **Solve for x**:
- To find x, subtract 155 from both sides:
\[ x = 200 - 155 \]
- Therefore:
\[ x = 45 \]

7. **Conclusion**:
- Arun scored 45 marks in Science.