DEPRECATED Representing relationships with matrices

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Problem

The price of produce depends on whether it is organically or conventionally grown. Below is a matrix that contains the cost of kale and spinach that are grown organically and conventionally. The rows represent whether it's conventionally or organically grown, while the columns represent whether it’s kale or spinach.
$\qquad \left[ \begin{array}{cc} 1.25 & 0.90 \\ 1.95 & 1.55 \end{array} \right]$
If a bundle of conventional kale costs dollar sign, 1, point, 25, how much does it cost to buy 3 bundles of organic kale and 1 bundle of organic spinach?
The vegetables will cost dollar sign
.