Explain solution RD Sharma class 12 Chapter 29 Linear Programming exercise 29.4 question 22
Answer:
Max Profit = Rs.116000 when 20 first class tickets and 180 economy class tickets are sold.
Hint:
Form Linear Equation and solve graphically.
Given:
An aero plane can carry a maximum of 200 passengers. A profit of Rs.400 is made on each first class ticket and a profit of Rs.600 is made on each economy class ticket. The airline reserves at least 20 seats of first class. However, at least 4 times as many passengers prefer to travel by economy class to the first class.
Solution:
Let required number of first class and economy class tickets be x and y respectively.
Each ticket of first class and economy class make profit of Rs.400 and Rs.600 respectively.
So, x ticket of first class and y tickets of economy class make profit of Rs.400x and Rs.600y respectively.
Let total profit be Z=400x+600y
Given, aero plane can carry a minimum of 200 passengers, so
Given, airline reserves at least 20 seats for first class, so
Also, at least 4 times as many passengers prefer to travel by economy class to the first class, so
Hence the mathematical formulation of the LPP is
Max Z=400x+600y
Subject to constraints
{Seats in both the classes cannot be 0}
Region represented by : the line x + y = 200 meets the axes at A(200,0), B(0,200). Region containing origin represents as (0,0) satisfies
Region represented by : line x=20 passes through (20,0) and is parallel to y-axis. The region to the right of the line x=20 will satisfy the in equation
Region represented by : line y=4x passes through (0,). The region above the line y=4x will satisfy the in equation
Region : it represents the first quadrant.
Scale: On y-axis, 1 big Division=100 units
On x-axis, 1 big Division=50 units
The corner points are C(20,80), D(40,160), E(20,180)
The values of Z at these corner as follows
Corner Points |
|
O |
0 |
C |
56000 |
D |
112000 |
E |
116000 |
The maximum value of Z is attained at E(20,180).
Thus, the max profit is Rs.116000 obtained when 20 first class tickets and 180 economy class tickets sold.