The video tutorial explains how to solve a word problem using the matrix method. It begins by setting up the problem with variables and equations, then represents these equations in matrix form. The tutorial covers finding the inverse of a matrix, calculating cofactors and determinants, and using the adjoint to find the solution. The final section includes calculations and concludes with the cost of each item per kg.

What is the primary method discussed in the video for solving word problems?

• Substitution Method

• Trial and Error

• Matrix Method

• Graphical Method

What are the given quantities in the problem setup?

• Cost of 4 kg onion, 3 kg wheat, 2 kg rice

• Cost of 3 kg onion, 2 kg wheat, 4 kg rice

• Cost of 3 kg onion, 4 kg wheat, 2 kg rice

• Cost of 2 kg onion, 3 kg wheat, 4 kg rice

What variable is assumed for the cost of 1 kg of onion?

• Y

• Z

• W

• X

How are the equations written in matrix form?

• As a 5x5 matrix

• As a 4x4 matrix

• As a 3x3 matrix

• As a 2x2 matrix

What is the formula for finding the inverse of a matrix?

• A = B * C

• X = A * B

• X = A inverse * B

• A = X * B

What is the first step in finding the cofactor of a matrix?

• Add all elements

• Subtract all elements

• Multiply all elements

• Eliminate rows and columns

What does a non-zero determinant indicate about a matrix?

• It is undefined

• It is non-singular

• It is zero

• It is singular

What operation is performed to find the adjoint of a matrix?

• Subtraction

• Multiplication

• Transposition

• Addition

What is the next step after finding the adjoint to calculate the inverse?

• Add the adjoint

• Multiply by determinant

• Divide by determinant

• Subtract the adjoint

What is the result of the matrix multiplication in the solution?

• 150, 250, 250

• 200, 300, 300

• 250, 400, 400

• 100, 200, 200