There were 35 students in a hostel. If the number of students increase...
Suppose the average expenditure was ? x.
Then total expenditure = 35x. When 7 more students join the mess, total expenditure = 35*+42.
Now. the average expenditure =
Now, we have
or, 35x+ 42 = 42x - 42
or, 7x = 84
Therefore, x = l 2
Thus the original expenditure of the mess = 35x12 = Rs. 420.
View all questions of this test
There were 35 students in a hostel. If the number of students increase...
Given Information:
- Initially, there were 35 students in a hostel.
- After the number of students increases by 7, the expenses of the mess increase by Rs. 42 per day.
- The average expenditure per head diminishes by Rs. 1.
Objective:
To find the original expenditure of the mess.
Solution:
Let's assume the original expenditure of the mess is 'x' Rs.
Step 1: Calculate the new average expenditure per head.
The original average expenditure per head can be calculated by dividing the original expenditure of the mess by the number of students:
Original average expenditure per head = x / 35 Rs.
After the number of students increases by 7, the average expenditure per head diminishes by Rs. 1. So, the new average expenditure per head can be calculated as follows:
New average expenditure per head = (x + 42) / 42 Rs.
According to the given information, the new average expenditure per head is Rs. 1 less than the original average expenditure per head:
(x + 42) / 42 = x / 35 - 1
Step 2: Solve the equation.
To solve the equation, we can cross-multiply:
35(x + 42) = 42(x / 35 - 1)
Simplifying the equation:
35x + 35(42) = 42x - 42(35)
35x + 1470 = 42x - 1470
Moving the variables to one side and the constants to the other side:
42x - 35x = 1470 + 1470
7x = 2940
Dividing both sides of the equation by 7:
x = 420
Conclusion:
The original expenditure of the mess is Rs. 420.