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Use matrix multiplication to answer an application question

Question 1 of 8

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Matrices \(A\) and \(B\) describe small items sold at school book-fair desks. The columns of \(A\) and the rows of \(B\) use the same item type order

A: Items sold

Rows, in order: Entry desk, Fiction desk

Columns, in order: Bookmarks, Postcards

\[A = \begin{bmatrix} 4 & 4 \\ 2 & 1 \end{bmatrix}\]

B: value for one unit of each item type

Rows, in order: Bookmarks, Postcards

Columns, in order: Sales value

\[B = \begin{bmatrix} \$1.15 \\ \$1.53 \end{bmatrix}\]
(a)2 marks

Use row-by-column multiplication to complete the labelled product \(AB\)

Rows: Entry desk, Fiction desk. Columns: Sales value ($)

\(AB\)
(b)1 mark

Interpret the entry in row 2, column 1 of \(AB\): Fiction desk and Sales value