(a)[2]
Calculate $(30\ \ 20)\begin{pmatrix}1.2\\2\end{pmatrix}-(40\ \ 30)\begin{pmatrix}-0.5\\3\end{pmatrix}$.
(b)[1]
Explain what your result in part (a) represents.
Mathematics 4024 · O Level · Algebraic manipulation
Algebraic manipulation — practice question
Across a two-week span, a shopkeeper notes how many packets of two distinct kinds of tea he sells and the profit earned from them. Matrices may be used to represent this information.