Question

A local hardware store sells three types of boxes; small, medium and large. The cost of the boxes are; small $10, medium $20 and large $30. In the previous week a total of 1200 boxes were sold resulting in proceeds of $20 000 for the week. The number of small boxes sold was equal to the sum of the medium and large boxes sold.

Use matrix methods to determine how many of each type of box was sold.

Answer 1

let x number of small box soldy number of medium box soldz number of large box sold
equation 1
x + y + z = 1200
equation 210x + 20y + 30 z = 20000
equation 3
x = y + z
then solve the equation simulataneouslyx = 600 small boxes were soldy = 400 medium boxes were soldz = 200 large boxes were sold