Today was a work period. We worked on old exam questions.

Richard needs some school supplies. In the following matrix, he compares the cost ($)
per package for the same three items from three different stores. These costs do not
include taxes.
store X store Y store Z
pencils 1.59 1.89 1.69
A= pens 1.79 1.49 1.99
notebooks 2.09 1.69 1.79

a) Calculate the cost per package including taxes. Show your work using matrix
operations. (GST = 6%, PST = 7%)

A x 1.13= 1.80 2.14 1.91
2.02 1.68 2.29
2.36 1.91 2.02

b) If Richard needs 2 packages of pencils, 1 package of pens, and 5 packages of
notebooks, at which store should he shop to get the lowest price? Show your work
using matrix operations.

1.80 2.14 1.91 storeX storeY storeZ
[2 1 5] x 2.02 1.68 2.29 = [17.42 15.51 16.22]
2.36 1.91 2.02

He should shop at store Y.

here's the link if you want:
http://www.edu.gov.mb.ca/k12/assess/archives/ap_mg_june_08.pdf