Question

then find the
The average salary of the teachers of a school is Rs. 3000. When salary of
two more teachers is included, the average salary reduces by Rs. 100 and
the total salary increased by Rs. 4000. Now, find the number of teachers.​

Answer 1

Answer:

Step-by-step explanation:Let the number of teachers be x

Sum of salaries=3000x

Now,3000x+4000/(x+2)=2900

3000x+4000=2900x+5800

1800=100x

x=18

Answer 2

$\Large{\underline{\sf{Answer}}}$

The total number of teachers initially was 18 after after adding two more teachers it become 20 .

$\Large{\underline{\sf{Given}}}$

• Average salary of total teachers= Rs 3000

• After adding 2 teachers average salary decreased by 100 rupees .

• And total salary increased by 4000 rupees.

Now let's assume that the total number of teachers was x and the sum of their salary was rupees y .

$\sf{ \implies \: \frac{y}{x} = 3000}$

$\sf{\implies y = 3000x \: eq \: 1st}$

Now after adding 2 new teachers .

→ Average salary = 3000-100 → 2900

→ Number of teachers = X+2

→ Total salary = y+4000 .

$\sf{ \implies \: \frac{y + 4000}{x + 2} = 2900}$

$\sf{\implies y + 4000 = (X+2)2900}$

$\sf { \implies \: y + 4000 = 2900x + 5800}$

Putting the value of y from eq. 1st

$\sf{\implies 3000 x+ 4000 = 2900x + 5800}$

$\sf{\implies 3000x - 2900x = 5800 - 4000}$

$\sf{\implies 100x = 1800}$

$\sf{X = \frac{1800}{100}}$

${ \underline{ \sf{ \implies \: x \: = 18}}}$

So the number of teachers is 18 .