Q11 of 54 Page 128

An electronic company records each type of entertainment device sold at three of their branch stores so that they can monitor their purchases of supplies. The sales in two weeks are shown in the following spreadsheets.


Find the sum of the items sold out in two weeks using matrix addition.

Here we consider the types of items sold along the column and the store in which they are stored along the rows


Thus week 1 and week 2 matrices can be written as


W1 = and W2 =


The sum of the items sold in two weeks is the sum of the above two matrices, which is sum of each corresponding elements of the two matrices


W1 + W2 =


⇒


TV DVD video CD


⇒ The sum of items sold in two weeks =


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