2025 DSS PRELIMS P1 Q25

At a school carnival, two different classes sold ice cream to raise funds. They sold in three different flavours: almond, blueberry and chocolate. Class A sold 60 almond ice cream, 80 blueberry and 50 chocolate. Class B sold 50 almond ice cream, 90 blueberry and 70 chocolate.

This information can be represented by the matrix \(P=\begin{pmatrix}60&80&50\\50&90&70\end{pmatrix}\).

1. The almond ice cream is sold at $1.20, the blueberry ice cream at $1.50, and the chocolate ice cream at $1.80. Represent these amounts in a 3 × 1 column matrix Q.[1]
2. Evaluate the matrix \(T=PQ\).[2]
3. State what each of the elements of \(T\) represents.[1]
4. Class A decides to donate 80% of their amount raised to an elderly home. Class B decides to donate 90% of their amount to the same elderly home. Write a matrix \(D\) such that the product \(DT\) will give the total amount donated.[1]