Question

Write an expression for the cost of buying p pens at R10 each and n notebooks at R15 each. If you buy 3 pens and 2 notebooks, calculate the total cost. (5 marks)

Answer 1

To express the cost of buying \( p \) pens at R10 each and \( n \) notebooks at R15 each, we can formulate the expression as follows:

\[
\text{Total Cost} = 10p + 15n
\]

Now, if you buy 3 pens and 2 notebooks, we can substitute \( p \) with 3 and \( n \) with 2 in the expression:

\[
\text{Total Cost} = 10(3) + 15(2)
\]

Calculating it step by step:

1. Calculate the cost of pens:
\[
10 \times 3 = 30
\]

2. Calculate the cost of notebooks:
\[
15 \times 2 = 30
\]

3. Now, add the costs together:
\[
30 + 30 = 60
\]

Thus, the total cost of buying 3 pens and 2 notebooks is R60.