There are triple the bananas as oranges. You also know that the eleven pieces of fruit cost $8.25, where bananas cost $0.50 each, oranges cost $0.75 each, and papayas cost $1.25 each.

Question

How many of each will be used?

Write the coefficient matrix equation.

Answer 1

Let x = the number of bananas purchased

y= the number of oranges purchased

And z = the number of papayas purchased

We know x=3y or x-3y=0

x+y+z=11

and .50x + .75y + 1.25z = 8.25.

The coefficient matrix can be

1, -3, 0, 0

1, 1, 1, 11

.50, .75, 1.25, 8.25