The average of all the 60 employees in an office is `₹12000` per month . If the number of executives is twice the number of non-executive employees , and average salary of executives is 15000 , then the average salary of all the non executive employees is :

Options

A. `₹9000`
B. `₹8000`
C. `₹6000`
D. Can't determined

Answer

To solve the problem step by step, we will use the information given in the question to find the average salary of non-executive employees.

### Step 1: Define the variables
Let:
- \( N \) = number of non-executive employees
- \( E \) = number of executive employees

According to the problem, the number of executives is twice the number of non-executives:
\[ E = 2N \]

### Step 2: Total number of employees
The total number of employees is given as 60:
\[ N + E = 60 \]

Substituting \( E \) from the previous step:
\[ N + 2N = 60 \]
\[ 3N = 60 \]

### Step 3: Solve for the number of non-executive employees
Now, divide both sides by 3:
\[ N = \frac{60}{3} = 20 \]

So, the number of non-executive employees is 20.

### Step 4: Calculate the number of executive employees
Now, using the relationship \( E = 2N \):
\[ E = 2 \times 20 = 40 \]

So, there are 40 executive employees.

### Step 5: Calculate the total salary of all employees
The average salary of all 60 employees is ₹12,000. Therefore, the total salary of all employees is:
\[ \text{Total Salary} = \text{Average Salary} \times \text{Total Employees} \]
\[ \text{Total Salary} = 12000 \times 60 = 720000 \]

### Step 6: Calculate the total salary of executive employees
The average salary of executive employees is ₹15,000. Therefore, the total salary of executive employees is:
\[ \text{Total Salary of Executives} = \text{Average Salary of Executives} \times \text{Number of Executives} \]
\[ \text{Total Salary of Executives} = 15000 \times 40 = 600000 \]

### Step 7: Calculate the total salary of non-executive employees
Now, we can find the total salary of non-executive employees by subtracting the total salary of executives from the total salary of all employees:
\[ \text{Total Salary of Non-Executives} = \text{Total Salary} - \text{Total Salary of Executives} \]
\[ \text{Total Salary of Non-Executives} = 720000 - 600000 = 120000 \]

### Step 8: Calculate the average salary of non-executive employees
Finally, we can find the average salary of non-executive employees by dividing the total salary of non-executives by the number of non-executives:
\[ \text{Average Salary of Non-Executives} = \frac{\text{Total Salary of Non-Executives}}{N} \]
\[ \text{Average Salary of Non-Executives} = \frac{120000}{20} = 6000 \]

Thus, the average salary of all the non-executive employees is **₹6000**.

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