Solution of Linear Programming Problems

IMPORTANT

Solution of Linear Programming Problems: Overview

This topic covers concepts, such as, Manufacturing Problems, Optimisation Problem, Condition of Infeasibility & Conflicting Constraints etc.

Important Questions on Solution of Linear Programming Problems

MEDIUM
IMPORTANT

For an LPP the objective function is Z=4x+3y and the feasible region determined by set of constraints(linear inequations) is shown in the graph.

Question Image

Which of the following statement is true?

HARD
IMPORTANT

What are conflicting constraints. Show that the LPP in which the objective function z=6x+4y is to be minimized subject to the constraints 3x+2y18 and 2x+y16 x0, y0 has infinitely many optimal solutions.

HARD
IMPORTANT

What are conflicting constraints. 

Show that the LPP of which two constraints are 3x-5y7 and 10y9+6x has no optimal solution.

MEDIUM
IMPORTANT

What are conflicting constraints. Show that if each of the infinitely many optimal solutions of an LPP with objective function z=ax+by, lies on the line 15 x+25 y=32 with 5a=3b.

MEDIUM
IMPORTANT

What are conflicting constraints. Find optimal solution of the following LPP, Maximize z=2x+3y subject to 5x+4y20, where x0, y0.

MEDIUM
IMPORTANT

What are conflicting constraints. 

Show that the optimal solution of the following LPP

Maximize z=5x+3y

Subject to, x+2y16,

0y3,

x0

lies on the straight line 2x+5y=32.

HARD
IMPORTANT

Solve z=2x+3y, subject to x+y62x+y16x0y0 graphically. Check whether it has feasible or infeasible solution.

HARD
IMPORTANT

Solve z=3x+2y, subject to x+y52x+y20x0y0 graphically. Check whether it has feasible or infeasible solution.

HARD
IMPORTANT

Solve z=2x+2y, subject to x+y5x+2y14x0y0 graphically. Check whether it has feasible or infeasible solution.

HARD
IMPORTANT

Solve z=x+2y, subject to x+y53x+y21x0y0 graphically. Check whether it has feasible or infeasible solution.

HARD
IMPORTANT

Solve z=4x+3y, subject to x+y62x+y20x0y0 graphically. Check whether it has feasible or infeasible solution.

HARD
IMPORTANT

An oil company has two depots, A and B, with capacities of 7000 L and 4000 L respectively. The company is to supply oil to three pumps, D, E, F, whose requirements are 4500 L, 3000 L, and 3500 L respectively. The distances in km between the depots and the petrol pumps are given in the following table:

  Distance in Km 

From 

To

A B
D 7 3
E 6 4
F 3 2

Assuming that the transportation cost per km is Rs 1 per litre, the delivery is scheduled in order that the transportation cost is minimum. What is the minimum transportation cost?

EASY
IMPORTANT

The feasible region of an LPP is shown in the figure. If z=3x+9y, then the minimum value of z occurs at 

Question Image

EASY
IMPORTANT

The corner points of the feasible region are 800, 400, 1050, 150, 600, 0. The objective function is P=12x+6y. The maximum value of P is

HARD
IMPORTANT

Reshma wishes to mix two types of food P and Q in such a way that the vitamin contents of the mixture contain at least 8 units of vitamin A and 11 units of vitamin B. Food P costs Rs.60/kg and Food Q costs Rs.80/kg. Food P contains 3 units/kg of vitamin A and 5 units/kg of vitamin B while food Q contains 4 units/kg of vitamin A and 2 units/kg of vitamin B. Determine the minimum cost of the mixture?

HARD
IMPORTANT

Find the maximum value of Z=7x+7y subject to the constraints.

x  0, y  0, x + y  2 and 2x + 3y  6.

HARD
IMPORTANT

A dietician wishes to mix two types of food, X and Y, in such a way that the vitamin contents of the mixture contains at least 8 units of vitamin A and 10 units of vitamin C. Food X contains 2 units/kg of vitamin A and 1 unit /kg  of vitamin C, while food Y contains 1 unit/kg of vitamin A and 2 units/kg of vitamin C. It costs 5 per kg to purchase the food X and 7 per kg to purchase the food Y. Determine the minimum cost of such a mixture.

HARD
IMPORTANT

The objective function Z=4x1+5x2, subject to 2x1+x27, 2x1+3x215, x23 & x1,x20 has minimum value at the point

HARD
IMPORTANT

Solution of the LPP Min. Z=5x+10y subject to: x+2y120, x+y60, x-2y0, x, y0 is

HARD
IMPORTANT

A small firm manufactures necklace and bracelets. The total number of necklace and bracelet that it can handle per day is at most 24. It takes 1hour to make a bracelet and half an hour to make a necklace. The maximum number of hours available per day is 16. If the profit on a necklace is 100 and that on a bracelet is 300, how many of each should be produced daily to maximize the profit? It is being given that at least one of each must be produced.